Living Architecture Monitor - Green Roofs for Healthy Cities
Living Architecture Monitor - Green Roofs for Healthy Cities
Living Architecture Monitor - Green Roofs for Healthy Cities
Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
GREEN ROOFS FOR HEALTHY CITIES<br />
WINTER<br />
VOLUMENO<br />
LIVING<br />
ARCHITECTURE<br />
MONITOR<br />
PLANTSFORHOTCOLD<br />
ANDDROUGHTS<br />
ORGANICVS<br />
INORGANIC?<br />
CREATINGHABITAT
LIVING<br />
ARCHITECTURE<br />
MONITOR<br />
WINTERVOLUMENO<br />
<strong>Living</strong> <strong>Architecture</strong> <strong>Monitor</strong> is published four times per year by<br />
<strong>Green</strong> <strong>Roofs</strong> <strong>for</strong> <strong>Healthy</strong> <strong>Cities</strong>* (www.greenroofs.org)<br />
Steven W. Peck<br />
Publisher & Founder<br />
speck@greenroofs.org<br />
416.971.4494 ext. 233<br />
Caroline Nolan<br />
Editor<br />
cnolan@greenroofs.org<br />
416.971.4494 ext. 231<br />
ARTDIRECTION<br />
IR&Co Inc.<br />
ADVERTISE<br />
416.971.4494 ext. 231 or advertise@greenroofs.org<br />
Rate card & insertion order <strong>for</strong>m are also available online at<br />
www.greenroofs.org/magazine<br />
SUBSCRIBE<br />
Subscriptions are included with membership to <strong>Green</strong> <strong>Roofs</strong> <strong>for</strong> <strong>Healthy</strong> <strong>Cities</strong>.<br />
Three levels of membership are available (in US dollars):<br />
1. Supporter Membership - $50<br />
2. Professional Membership - $149<br />
3. Corporate Memberships - $750 to $4800<br />
To learn more about our various membership levels and their various other benefits<br />
please visit our website at: www.greenroofs.org<br />
Change address<br />
circulation@greenroofs.org or mail or fax to address below.<br />
CONTACTUS<br />
406 King Street East, Toronto, Ontario M5A 1L4 Canada<br />
Tel. 416.971.4494 Fax 416.971.9844<br />
www.greenroofs.org<br />
SUBMITNEWSSTORYIDEASORFEEDBACK<br />
We welcome letters to the editor, feedback and comments, as well as story<br />
ideas and industry news about people, products and projects <strong>for</strong> consideration<br />
in upcoming editions of the <strong>Living</strong> <strong>Architecture</strong> <strong>Monitor</strong>: editor@greenroofs.org.<br />
<strong>Green</strong> <strong>Roofs</strong> <strong>for</strong> <strong>Healthy</strong> <strong>Cities</strong> — North America, Inc. was founded in 1999 as a<br />
small network of public and private organizations and is now a rapidly growing<br />
501(c)(6), not-<strong>for</strong>-profit industry association. Our mission is to increase the<br />
awareness of the economic, social and environmental benefits of green roofs<br />
and green walls, and other <strong>for</strong>ms of living architecture through education,<br />
advocacy, professional development and celebrations of excellence.<br />
Members of Board<br />
Peter Lowitt, chair, Devens Enterprise Commission<br />
Dan Sloan, secretary, McGuire Woods LLP<br />
Richard J. Buist, Landscource Organixs Ltd.<br />
Jeffrey Bruce, Jeffery L. Bruce & Co. LLC<br />
Peter D’Antonio, Sika Sarnafil Inc.<br />
Karen Moyer, City of Waterloo (Ontario)<br />
*<strong>for</strong>merly the <strong>Green</strong> Roof Infrastructure <strong>Monitor</strong><br />
Disclaimer: Contents are copyrighted and may not be reproduced without written consent. Every ef<strong>for</strong>t has<br />
been made to ensure the in<strong>for</strong>mation presented is accurate. The reader must evaluate the in<strong>for</strong>mation in<br />
light of the unique circumstances of any particular situation and independently determine its applicability.
COLD<br />
What can we learn from the climate characteristics of<br />
Nordic green roofs?<br />
By Kerry Ross<br />
<br />
<br />
<br />
<br />
<br />
FROMTHEFOUNDER<br />
AVISIONFORTHEFUTURE<br />
By Steven W. Peck<br />
STRATA—PEOPLEPRODUCTS&PROJECTS<br />
ALIVINGLABORATORY<br />
Students and scientists team up on two green roofs at<br />
New York City’s Ethical Culture Fieldston School.<br />
GROUND-BREAKINGSUSTAINABLESITES<br />
INITIATIVELAUNCHED<br />
ASLA, Lady Bird Johnson Wildflower Center and<br />
others developing voluntary standards <strong>for</strong> sustainable<br />
land use and landscaping practices.<br />
REVIEW<br />
Books: ALSA’s Case Study; Ian McHarg — Conversations<br />
with Students; Busby: Learning Sustainable<br />
Design; and Alessandro Rocca’s Natural <strong>Architecture</strong><br />
ONTHEROOFWITH…<br />
AQ&AWITHTHELEGENDARYLANDSCAPE<br />
ARCHITECTCORNELIAHAHNOBERLANDER<br />
By Caroline Nolan<br />
<br />
<br />
<br />
<br />
DROUGHT<br />
Evaluating the per<strong>for</strong>mance of green roof plants and<br />
growing medium.<br />
By Dr. Bill Retzlaff, Dr. Susan Morgan, Kelly Luckett<br />
and Vic Jost<br />
CREATINGHABITAT<br />
BYDESIGN<br />
A new process model can help you make the right<br />
decisions when trying to restore habitats <strong>for</strong> a specific<br />
species on green roofs and wall projects.<br />
By Dr. Reid Coffman and Alison Thurmond<br />
POLICY<br />
SEATTLE’S“GREENFACTOR”<br />
A new urban landscaping policy is creating an incentive<br />
<strong>for</strong> more green roofs and walls in this coastal city.<br />
By Lillian Mason and GRHC staff<br />
”BUSHTOPS”DOWNUNDER<br />
South Australian government’s green wall and green<br />
roof incentive policies are bringing the “bush” back<br />
into Adelaide.<br />
By Graeme Hopkins & Christine Goodwin<br />
<br />
<br />
<br />
PROJECT<br />
ISLANDPARADISE<br />
An award-winning Ontario residential project — three<br />
years later.<br />
By Flavia Bertram<br />
BESTPRACTICE<br />
GROWINGMEDIA—THEORGANICQUESTION<br />
Rick Buist & Chuck Friedrich face off on how much<br />
organic — if any — is best <strong>for</strong> optimal per<strong>for</strong>mance.<br />
NATIVEPLANTRESEARCH<br />
IMPACTOFGROWINGMEDIAONPRAIRIEGRASSES<br />
Thinking like a prairie in Lincoln, Nebraska.<br />
By Richard K. Sutton<br />
<br />
<br />
<br />
GRHCUPDATE<br />
GREENWALLTECHNOLOGYCLIMBING<br />
By Lillian Mason and GRHC staff<br />
OMAHAWELCOMESOPPORTUNITYTOBUILD<br />
MOREGREEN ROOFS<br />
Stormwater management among topics discussed at recent<br />
Nebraskan-based Local Market Development Symposium.<br />
By Kent E. Holm<br />
SYMPOSIUMIGNITESGREENROOF&WALL<br />
MOMENTUMINATLANTA<br />
From architects to policymakers — the finest<br />
professionals gathered to brainstorm an action plan<br />
<strong>for</strong> more green roofs in Georgia’s capital city.<br />
By Lillian Mason & GRHC staff<br />
<br />
NATIVESURVIVORS<br />
Insights from study conducted by the New England Wild<br />
Flower Society in partnership with the Massachusetts<br />
College of Art.<br />
By Ron M. Wik<br />
<br />
FROMTHEACCREDITATIONSUB-COMMITTEE<br />
First <strong>Green</strong> Roof Professional accreditation exam<br />
planned <strong>for</strong> 2009 conference in Atlanta, Georgia.<br />
By Hazel Farley<br />
<br />
EXTREMECONDITIONS<br />
HOT&HUMID<br />
What plants work best in tropical and subtropical climates?<br />
By Steve Skinner<br />
<br />
ONSPEC<br />
FROMWHEREIAGREENROOFERSIT<br />
The role of the landscaper on green roof projects.<br />
By Kurt Horvarth
FROMTHEFOUNDER<br />
AVISIONFOR<br />
THEFUTURE<br />
IMAGINEASWEDOOURCOLLECTIVE<br />
POWERTOCREATEHEALINGRESTORATIVE<br />
BUILDINGSDESIGNEDWITHLIVING<br />
ARCHITECTUREPRINCIPLES<br />
THEEDITTBUILDINGINSINGAPORE<br />
Image courtesy of TR Hamzah & Yeang Sdn Bhd
THEGROWINGMEDIA&PLANTISSUE<br />
Welcome to the <strong>Living</strong> <strong>Architecture</strong> <strong>Monitor</strong>. We are dedicated<br />
to bringing you the best research, policy and practices<br />
focused on the integration of living and non-living elements<br />
in and around buildings. <strong>Living</strong> architecture is the pathway to<br />
making a more fundamental shift towards the creation of<br />
healing, restorative high-per<strong>for</strong>mance buildings — and by<br />
extension, healthier, more liveable communities.<br />
In essence, healing, restorative, high-per<strong>for</strong>mance buildings give back<br />
more than they use over their lifecycles: producing a surplus of renewable<br />
energy, cleaner water, improved air quality and aesthetics,<br />
the very foundation <strong>for</strong> vibrant biological diversity and the greater<br />
physical and emotional well-being of humans.<br />
<strong>Green</strong> roofs and green walls are two key elements of living<br />
architecture that are gaining more widespread acceptance<br />
throughout North America. These living architectural <strong>for</strong>ms allow<br />
<strong>for</strong> unparalleled benefits at different scales — at the site level<br />
(aesthetics, stormwater quality and quantity): at the building level<br />
(energy savings, noise reduction, membrane durability, recreation<br />
space, urban food production, improved PV efficiency, biodiversity,<br />
advertising, marketability, improved investment value); at the community<br />
level (improved aesthetics, air quality benefits, cooling<br />
urban heat island, noise abatement, educational opportunities,<br />
community food production, psychological benefits); and the wider<br />
region (reducing greenhouse gases, supporting ecological diversity)<br />
— and this list is by no means complete.<br />
We need to re-imagine buildings as small ecosystems, nestled within<br />
the larger bioregions of our communities. McDonough and Braungart,<br />
in Cradle to Cradle, call <strong>for</strong> a shift toward “eco-effectiveness” and<br />
suggest we adopt a new design assignment set out to create “buildings,<br />
that like trees, produce more energy than they consume and purify<br />
their own wastes.” Restorative buildings won’t add more stress to<br />
existing infrastructure, such as coal-fired plants and the lengthy<br />
transmission wires that supply power; or our overtaxed water and<br />
wastewater treatment plants that regularly discharge vast quantities<br />
of raw sewage into our lakes, rivers and oceans.<br />
filtered through a series of ‘John Todd like’ facades and vegetated-terraces.<br />
The indigenous vegetation areas are designed to be continuous<br />
and to ramp upwards from the ground plane to the uppermost floor in<br />
a linked landscaped ramp. The design’s planted-areas constitute 3,841<br />
sq.m., a ratio 1:0.5 of gross useable area to gross vegetated area. Rainwater<br />
will be cleansed, stored in the basement and provide water <strong>for</strong><br />
toilets and irrigation <strong>for</strong> the living architectural features, an amenity to<br />
building occupants on every floor of the 26-story structure.<br />
If living architecture is to blossom as a practice this century, we also<br />
need to understand the full contribution that living systems offer —<br />
economic, social, psychological and environmental and ensure that<br />
these are reflected, rather than discounted in the marketplace.<br />
The vehicle <strong>for</strong> this change is through policies, regulations, and standards<br />
and investment. At a city-wide scale, we need to better understand<br />
the economic benefits of widespread living architecture in order<br />
to help facilitate the public resources required to fully support these<br />
developments. As our industry continues to rapidly grow, we can trans<strong>for</strong>m<br />
the building industry into a fundamental <strong>for</strong>ce <strong>for</strong> sustainability.<br />
<strong>Green</strong> <strong>Roofs</strong> <strong>for</strong> <strong>Healthy</strong> <strong>Cities</strong> is dedicated to bringing about the<br />
rapid shift towards a living architecture and the creation of healing<br />
restorative buildings. Through this new publication, we will work<br />
tirelessly to bring you, our members, the latest in research, product<br />
developments, standards, tools, innovative designs and new policies<br />
that support your ability to make a lasting life-long contribution<br />
towards sustainable building.<br />
Sincerely yours,<br />
<strong>Living</strong> architecture is exemplified in Ken Yeang’s remarkable EDITT skyscraper<br />
in Singapore, designed from an ecological approach (pictured<br />
left). The building will be 55 per cent water self-sufficient, produce<br />
renewable energy and process wastewater. Captured rainwater is<br />
Steven W. Peck<br />
Founder and President<br />
LIVING ARCHITECTURE MONITOR WINTER
STRATA<br />
KUDOS<br />
PRIZE-WINNINGPROJECTS<br />
At <strong>Green</strong> <strong>Roofs</strong> <strong>for</strong> <strong>Healthy</strong> <strong>Cities</strong>, we love to<br />
celebrate excellence in green roof and wall<br />
design — so our hats go off to the following individuals<br />
and organizations <strong>for</strong> their recent<br />
achievements:<br />
PRESERVINGSTORMWATERINPHILLY<br />
Pennoni Associates, a consulting engineering<br />
firm headquartered in Philadelphia, Pennsylvania<br />
won the award <strong>for</strong> Stormwater Best Management<br />
Practices <strong>for</strong> its green roof design on<br />
The Radian, located on Walnut Street in<br />
Philadelphia. The honors came from the<br />
Philadelphia Water Department, Offices of the<br />
Watersheds, a statewide program that recognizes<br />
innovative stormwater best management<br />
practices. The project, which integrates green<br />
roof areas into the public terrace level of a<br />
mixed-use facility that includes lower level<br />
retail space and a 13-story residential tower<br />
<strong>for</strong> student apartments, broke ground in Mary<br />
2007 and will open this August. The innovative<br />
strategy <strong>for</strong> stormwater management drains<br />
runoff from impervious areas of the roof into<br />
the green roof structure, maximizing water<br />
retention on the roof while controlling the<br />
release rate into two underground stormwater<br />
management basins. Additionally, the plant<br />
design of the green roof will serve as a valued<br />
amenity to residents and the community at<br />
large. Erdy McHenry <strong>Architecture</strong> was the<br />
project architect while <strong>Roofs</strong>capes, Inc. served<br />
as subconsultant to Pennoni and provided key<br />
technical expertise <strong>for</strong> the green roof design.<br />
GREENINGCALGARY<br />
On Nov. 1, 2007, the city of Calgary’s<br />
Mayor’s Urban Design Awards took place<br />
with eight winners and four honourable<br />
mentions in a variety of categories. A<br />
conceptual entry, Grey to <strong>Green</strong>: <strong>Green</strong>ing<br />
Calgary One Roof at a Time, was jointly<br />
submitted by Kerry Ross, an architectural<br />
consultant with IBI Group in Calgary and<br />
Kelly Learned of Cochrane, Alberta, earned<br />
an honourable mention and special acknowledgement<br />
by Juror Shannon Nichol<br />
of the international landscape architecture<br />
firm, Gustafson Guthrie Nichol. Their<br />
entry illustrated how a green roof on one<br />
of Calgary’s landmarks, the Municipal<br />
Building, could set the tone <strong>for</strong> the region<br />
in terms of becoming a green roof<br />
technology leader.<br />
BELOWThe award-winning Radian in Philadelphia was recognized <strong>for</strong> its innovative stormwater management strategy. “This project is an example of how ecology,<br />
economics and aesthetics can be balanced to satisfy not only the owner and the users of the building, but also broader environmental goals,” says Marc Morfei,<br />
Philadelphia senior landscape architect.<br />
Renderings: Erdy McHenry <strong>Architecture</strong><br />
COMINGUP<br />
The Toronto Botanical Garden will host a green roof conference on Feb. 21, 2008. The event’s<br />
conference workshops will cover design, plants, biodiversity and technical considerations. Paul<br />
Kephart of Rana Creek will be a speaker, as well as the instructor <strong>for</strong> GRHC’s Ecological Design<br />
Course to be held in the morning of Feb. 22, also at the Botanical Gardens. For in<strong>for</strong>mation<br />
about the event, please email greenroof@logistix.com or see their website at www.torontobotanicalgarden.ca/greenroof.<br />
Further in<strong>for</strong>mation and registration details about GRHC’s Ecological Design course on Feb. 22<br />
can be found at www.greenroofs.org<br />
NEWS<br />
WANTED!<br />
We want to hear about your<br />
announcements (deals and projects<br />
completed); people moves; awards;<br />
and books and events. Send us an email<br />
at editor@greenroofs.org and your<br />
news may end up in Strata <strong>for</strong> our next<br />
issue. Please include photographs or<br />
images if applicable.<br />
<br />
LIVING ARCHITECTURE MONITOR<br />
WINTER
THEGROWINGMEDIA&PLANTISSUE<br />
ALIVINGLABORATORY<br />
STUDENTSOFALLAGESAREGETTINGANEDUCATION—ANDLEARNINGWHATIT’SLIKE<br />
TOCONDUCTRESEARCHALONGSIDECOLUMBIAUNIVERSITYSCIENTISTSATOPA NEW<br />
YORKCITYMIDDLESCHOOL’STWOGREEN ROOFS<br />
Students at New York City’s Ethical Culture<br />
Fieldston School will soon be applying their<br />
science studies towards green roof research.<br />
The recent $75 million renovation of the middle<br />
school has incorporated green building<br />
design and two green roofs. Dr. Stuart Gaffin,<br />
associate research scientist at The Center <strong>for</strong><br />
Climate Systems Research at Columbia<br />
University in New York and Dr. Mathew<br />
Palmer, a lecturer with the Department of<br />
Ecology, Evolution and Environmental Biology,<br />
also at Columbia University, spearheaded the<br />
research and study of the two roofs, both different<br />
in purpose and design.<br />
Fieldston made available its two green roofs<br />
<strong>for</strong> Columbia’s research, which in turn will<br />
present unusual opportunities <strong>for</strong> the<br />
school’s science teachers from grades<br />
one through 12.<br />
“There are many different technological<br />
aspects to green building design but none of<br />
them offers the educational richness of green<br />
roofs,” says Gaffin, who is in charge of the<br />
research at the school’s top-level roof. “<strong>Green</strong><br />
roofs can be used to teach physics, climatology,<br />
hydrology, biology, ecology, chemistry<br />
and so on. One could never develop such a<br />
far-reaching curriculum, around say, solar<br />
panels or energy-efficient windows.” His own<br />
“ There are many different technological aspects to green building design but none of<br />
them offers the educational richness of green roofs. <strong>Green</strong> roofs can be used to<br />
teach physics, climatology, hydrology, biology, ecology, chemistry and so on.”<br />
Dr. Stuart Gaffin, research scientist, Columbia University<br />
research centers on the energy benefits of<br />
Fieldston’s green roof with New York’s energy<br />
and water issue needs in mind.<br />
Columbia’s research on the top-level roof is<br />
conducted using a weather tower, multiple<br />
sets of soil moisture and temperature probes,<br />
an albedometer and plant foliage temperature<br />
sensors. The albedometer consists of<br />
two back-to-back pyranometers, a device<br />
designed to measure natural sunlight radiant<br />
energy, manufactured by Kipp and Zonen.<br />
“With the data we are collecting and subsequent<br />
analysis, much of which will be done by<br />
the students, I hope we can produce findings<br />
<strong>for</strong> an ‘optimal’ green roof design that maximizes<br />
environmental benefits at the lowest<br />
cost,” explains Gaffin. “This will help spur<br />
their adoption by New York City and elsewhere.”<br />
The lower level roof of the school, planted in<br />
part by Fieldston’s students last October, was<br />
designed to be a more interactive site with<br />
three different types of plant communities. In<br />
addition to a traditional mix of Sedum<br />
species, two native, diverse grassland communities<br />
were planted. One of these communities<br />
was modeled on the Hempstead Plains,<br />
a prairie-like grassland from Long Island<br />
which has been almost completely lost due to<br />
urban and suburban development. The other<br />
native community is modeled on grasslands<br />
native to the Hudson Valley’s rocky hilltops<br />
with shallow soil, droughts and harsh wind, a<br />
climate very similar to that on the roof. Students<br />
will follow the success of the different<br />
plantings through time and will compare<br />
ecological processes like pollination and the<br />
development of the soil between the three<br />
plant communities.<br />
“If we can learn how to make native plant<br />
communities succeed on green roofs, it will<br />
add immensely to the value of those roofs as<br />
ecological restoration projects, habitat <strong>for</strong><br />
other species and living laboratories <strong>for</strong><br />
schools,” says Palmer.<br />
The students at Fieldston created a video<br />
detailing the building process of the second<br />
roof which can be viewed at www.ecfs.org <br />
By Lillian Mason & GRHC staff<br />
LIVING ARCHITECTURE MONITOR WINTER
STRATA<br />
GROUND-BREAKING<br />
SUSTAINABLESITES<br />
INITIATIVELAUNCHED<br />
ASLALADYBIRDJOHNSONWILDFLOWERCENTERAND<br />
OTHERSAREDEVELOPINGVOLUNTARYSTANDARDSFOR<br />
SUSTAINABLELANDUSEANDLANDSCAPINGPRACTICES<br />
The American Society of Landscape Architects<br />
(ASLA), the Lady Bird Johnson Wildflower<br />
Center, the United States Botanic<br />
Garden, and other stakeholders are working<br />
under the umbrella of the Sustainable Sites<br />
Initiative to develop voluntary standards and<br />
guidelines related to sustainable land use and<br />
landscaping practices.<br />
The initiative was established to “identify the<br />
gold standards in sustainable landscape design<br />
and marry them to a practical, real-world<br />
approach so that designers, planners,<br />
builders, and developers can utilize them,”<br />
says Nancy Somerville, executive vice president<br />
and CEO of the ASLA.<br />
In a preliminary report published in November<br />
2007, a committee composed of 32 professionals<br />
practicing across a variety of landscape<br />
related disciplines identified a series of design<br />
goals and methods of achieving and monitoring<br />
a site’s ability to satisfy these objectives. The<br />
group further recommended integrated design<br />
strategies as a means to “harness natural<br />
processes to provide environmental benefits.”<br />
The guidelines are scheduled <strong>for</strong> release in<br />
May 2009 and will be incorporated into the<br />
USGBC’s LEED® system.<br />
For more in<strong>for</strong>mation or to participate in the<br />
review process visit www.sustainablesites.org.<br />
GREENGRID<br />
INSTALLS<br />
LARGEST<br />
MODULAR<br />
ROOFIN<br />
NORTH<br />
AMERICA<br />
A 2.3 acre modular green roof, the largest of<br />
its kind in North America, covers the new<br />
court at Upper Providence shopping center<br />
in Montgomery County, Pennsylvania. The<br />
<strong>Green</strong>Grid® modules were installed in early<br />
2007 thanks to a joint venture between Gambone<br />
Development, Inc. and The Highland<br />
Development Group, Ltd.<br />
WASHINGTONDCSUPPORTSGREEN<br />
ROOFDEMONSTRATIONPROJECTS<br />
Through a grant from the District Department<br />
of the Environment, Watershed Protection<br />
Division, DC <strong>Green</strong>works, a<br />
preeminent green roof organization in the<br />
area, is subsidizing $3 per square foot of<br />
green roof demonstration projects.<br />
“This broadly available subsidy is generating<br />
a interest from a wider variety of developers<br />
than other incentives in the DC area.<br />
It is effectively helping mainstream building<br />
and land owners test out this progressive<br />
technology that wouldn’t otherwise have<br />
access to green roof funding,” says Sheila<br />
“This broadly available<br />
subsidy is…effectively<br />
helping mainstream<br />
building and land owners<br />
test out this progressive<br />
technology that wouldn’t<br />
otherwise have access to<br />
green roof funding.”<br />
Sheila Hogan, DC <strong>Green</strong>works, Washington, DC<br />
Hogan, executive director of DC<br />
<strong>Green</strong>works.<br />
In order to qualify an extensive or intensive<br />
project must be in D.C., can be new construction<br />
or retrofit, and on buildings with a<br />
footprint under 5,000 square feet or larger,<br />
in cases where the supporting structure<br />
was built prior to 1988. The program’s next<br />
deadline is February 15, 2008; others will<br />
be announced when determined.<br />
For further in<strong>for</strong>mation and the application <strong>for</strong>m<br />
visit: www,dcgreenworks.org.<br />
<br />
LIVING ARCHITECTURE MONITOR<br />
WINTER
GREENROOFSGO<br />
EXTREME—ANDPRIMETIME<br />
THEGROWINGMEDIA&PLANTISSUE<br />
It was Tuesday in April 2007 when<br />
Kelly Luckett got the call. A construction<br />
manager from the top show, Extreme<br />
Makeover Home Edition, asked if Luckett’s<br />
company, St. Louis-based <strong>Green</strong> Roof<br />
Blocks, could provide green roof modules<br />
<strong>for</strong> a green roof they were planning on a<br />
fully sustainable house they were building<br />
<strong>for</strong> a needy family in Pinon, Arizona on a<br />
Navaho Reservation. Luckett said he would<br />
be pleased to help, then came the kicker:<br />
the construction manager needed fully<br />
grown-out modules by that Sunday —<br />
just four days away.<br />
Under normal circumstances, it would take<br />
three to four weeks to deliver fully grown out<br />
modules, but Luckett was undeterred — even<br />
in the early spring. Saying yes, he quickly<br />
turned to his team on to the company’s research<br />
plots. “We could barely scrape together<br />
the number of square footage they<br />
needed — 200-modules, about 400 square<br />
feet in total,” he remembers. With plants<br />
ready, then came the real challenge — getting<br />
the modular plants, based in St. Louis, Missouri,<br />
to Pinon, Arizona — in just days. “No<br />
commercial freight carriers would commit to<br />
timelines, so we wound up putting it all into a<br />
rental truck and a staff member drove it<br />
across the country,” says Luckett.<br />
Luckett and his business partner both took<br />
time off to help out on the rapid installation<br />
of the green roof, bringing along their children<br />
<strong>for</strong> the once-in-a-lifetime experience.<br />
He was joined by another seasoned green<br />
roof professional, Dr. Bill Retzlaff, associate<br />
professor and chair of the Department of<br />
Biological Sciences Environmental Sciences<br />
Program at Southern Illinois University Edwardsville<br />
in Illinois.<br />
A hectic schedule, but well worth it, says<br />
Luckett, especially at the moment of the big<br />
“reveal” when the new house was unveiled<br />
<strong>for</strong> the worthy family. “It was a very emotional<br />
moment,” says Luckett, who, like every<br />
other contributor to the house, donated all<br />
his materials and time to make this dream<br />
house a reality <strong>for</strong> a very special family.
REVIEW<br />
TWISTINGNATURE<br />
Drawing on the works of artists dedicated to<br />
the use of natural materials — trees, wood,<br />
bamboo and pebbles — Alessandro Rocca’s<br />
Natural <strong>Architecture</strong> locates its readers at the<br />
intersection of art, architecture and ecology.<br />
The artists are all linked together by their desire<br />
to create incredibly complex installations<br />
while minimizing their effect on the environment<br />
in which they are created. Most employ<br />
basic artistic techniques and rely on manual<br />
labor to create awe-inspiring structures that<br />
will inevitably disintegrate but which raise lingering<br />
questions about our ways of inhabiting<br />
space. (Princeton Architectural Press, 2007)<br />
STRIKINGTHERIGHTBALANCE<br />
In an industry as new and multidisciplinary as<br />
the living architecture field, it is rare to get a<br />
project’s whole story. Not so anymore, Christian<br />
Werthmann’s <strong>Green</strong> Roof — A Case Study<br />
provides a comprehensive account of the<br />
American Society of Landscape <strong>Architecture</strong>’s<br />
green roof, in which Landscape Architects<br />
Michael Van Valkenburgh Associates<br />
and the Conservation Design Forum were<br />
charged with the task of maximizing both aesthetics<br />
and environmental per<strong>for</strong>mance. For<br />
the novice, the book demystifies every aspect<br />
of green roofing; <strong>for</strong> the seasoned professional,<br />
it allows <strong>for</strong> detailed examination of<br />
the design methodologies, construction techniques<br />
and maintenance practices employed<br />
to achieve these lofty goals. In an interview<br />
between the author and Van Valkenburgh,<br />
the designer placed emphasized the importance<br />
of striking the right balance. Hopefully,<br />
this book will help others do the same.<br />
(Princeton Architectural Press, 2007)<br />
ADAPTATION<br />
Ian McHarg, the author of the ecological design<br />
classic Design with Nature, has greatly<br />
trans<strong>for</strong>med the approach to and understanding<br />
of land-use planning and landscape architecture.<br />
Ian McHarg — Conversations with<br />
Students: Dwelling in Nature rearticulates the<br />
guiding principles of the “McHarg Method,”<br />
an interdisciplinary approach to land use design<br />
rooted in the notion that “creativity has<br />
permeated the evolution of matter and life,<br />
and actually is indispensable <strong>for</strong> the survival<br />
of the system.” He goes on to lay out the tools<br />
needed <strong>for</strong> the analysis and execution of<br />
“creative fitting,” a process driven by the<br />
theory that “any system is required to find<br />
of all environments the most fit, to adapt<br />
that environment, and to adapt itself.”<br />
(Princeton Architectural Press, 2007)<br />
BUSBY’SVISION<br />
Busby and Associates Architects are known<br />
<strong>for</strong> buildings that combine a Modernist aesthetic<br />
with environmentally responsive and<br />
integrated design strategies. Busby: Learning<br />
Sustainable Design profiles twelve of the<br />
firm’s projects (which coincidentally draw<br />
upon the theoretical framework of Ian<br />
McHarg’s Design with Nature), highlighting<br />
their contribution to the development of new<br />
green building per<strong>for</strong>mance standards. The<br />
book, produced in collaboration with heavyweights<br />
David Suzuki (<strong>for</strong>eward) and editors<br />
Jim Taggart and Kathy Wardle, will serve the<br />
interests of those interested in the theory,<br />
practice and direction of the sustainable<br />
design industry, especially the need <strong>for</strong> multidisciplinary<br />
collaboration. As Taggart notes:<br />
“Optimizing per<strong>for</strong>mance depends on a critical<br />
appreciation of the interdependence of structure,<br />
<strong>for</strong>m, envelope design and environmental<br />
systems.” (Janam Publications Inc., 2007)<br />
By Flavia Bertram
Photos courtesy Elisabeth Whitelaw<br />
ONTHEROOFWITH…<br />
CORNELIAHAHNOBERLANDERCMFCSLAFASLA<br />
By Caroline Nolan<br />
Cornelia Hahn Oberlander, born in Germany in 1924, obtained a BA<br />
from Smith College in 1944 and was one of the first women to<br />
graduate from Harvard University’s School of Design with a degree in<br />
landscape architecture in 1947. She worked with Louis I. Kahn and<br />
Oscar Stonorov in Philadelphia, and landscape architect Dan Kiley in<br />
Vermont, be<strong>for</strong>e moving to Vancouver to establish her own practice in<br />
1953, Cornelia Hahn Oberlander Landscape Architects.<br />
Her career is legendary.<br />
The 84-year-old is well-known <strong>for</strong> such extraordinary, pioneering works<br />
including “Robson Square” — the provincial government courthouse<br />
complex in Vancouver, a three-block green roof designed in collaboration<br />
with the architect Arthur Erickson (1974–81); the National Gallery<br />
of Canada, with architect, Moshe Safdie; University of British Columbia’s<br />
(UBC) Museum of Anthropology, also with Arthur Erickson<br />
(1975–76); the Canadian Chancery in Washington DC, also with Arthur<br />
Erickson (1989); the spectacular 28,000 square-foot semi-intensive<br />
roof on Moshe Safdie’s Vancouver Public Library (1995); and the Northwest<br />
Territories Legislative Assembly Building in Yellowknife, Canada<br />
with Matsuzaki Wright Architects and Gino Pin Architects (1995).<br />
She has received numerous awards including the prestigious Order of<br />
Canada in 1990; several honorary degrees from University of British<br />
Columbia (UBC), Simon Fraser University, Ryerson University and<br />
Smith College; a commemorative Medal <strong>for</strong> the 125th Anniversary of<br />
the Confederation of Canada in 1992; the Royal Architectural Institute<br />
of Canada Allied Medal in 1995; and an honorary membership to the<br />
Architectural Institute of BC as well as life membership in the British<br />
Columbia Society of Landscape Architects.<br />
Cornelia, a true pioneer of socially conscious and sustainable<br />
landscape design, has collaborated with internationally acclaimed<br />
architects, including Renzo Piano on public projects in the United<br />
States and Canada. We caught up with Oberlander in Vancouver<br />
late last year.<br />
LIVING ARCHITECTURE MONITOR WINTER
ONTHEROOFWITH…<br />
Q: The Germans have a wonderful sense of stewardship <strong>for</strong> nature<br />
and, indeed, created the green roof concept in the first place.<br />
Do you feel your heritage has influenced your work?<br />
A: Well, when I was 15, we landed in New York from Germany in<br />
1939, be<strong>for</strong>e the war, because my mother thought it was <strong>for</strong> us. A<br />
year and a half later, she came down from breakfast one day and<br />
said to me and my sister, ‘This place is too materialistic <strong>for</strong> you girls<br />
— all you are thinking about is sweaters and skirts. When you come<br />
new to a country you have to till the soil.’ She then whisked us in<br />
our wooden-bodied Ford Station wagon up to northern New Hampshire<br />
and that’s where I grew up. She was trained as a horticulturalist<br />
and created a Victory Garden to grow vegetables during the war<br />
and so, that’s how I grew up.<br />
Q: You have practiced “living architecture” be<strong>for</strong>e the term even<br />
existed — what does the term mean to you now?<br />
A: <strong>Living</strong> architecture means that the building is healthy and the land<br />
is healthy and that you are contributing to the biomass of the city,<br />
namely to make the air cleaner. I feel that if you have chosen the<br />
profession of landscape architecture, you have a duty to listen to what<br />
the times bring. It’s not what I was taught at Harvard way back when,<br />
necessarily, but all about what we must make of the land today. I’ve<br />
always looked to the future.<br />
Q: How has landscape architecture profession changed since you<br />
established your own practice in 1953?<br />
A: Well, the industry was non-existent then. You hoped <strong>for</strong> the best,<br />
that the building wouldn’t fall down! But I was already at Harvard realizing<br />
I could not work in a vacuum — that I would have to work in collaboration<br />
with architects.<br />
Q: Early in your career, did you ever imagine you would ever see the<br />
mainstreaming of green roofs as is happening now?<br />
A: Well, I had hoped it would happen. The municipal bylaws and the<br />
building bylaws of every city must include green roofs. We have not<br />
reached this goal yet.<br />
MOSHESAFDIE’SVANCOUVERPUBLICLIBRARY<br />
Q: You are retrofitting one of your most important and noted<br />
projects, Vancouver’s Robson Square — what is being done and why?<br />
A: Well, after 35 years it was time. In 1976, the waterproofing membrane,<br />
or EPDM, was guaranteed <strong>for</strong> 20 years, and it lasted <strong>for</strong> 35<br />
years. So that had to be renewed, but on top of that, the province of<br />
British Columbia demanded seismic upgrading <strong>for</strong> the whole building,<br />
and so this is being done at present and with it, came an in-depth<br />
analysis of the plant materials which were possible to keep. We lifted<br />
out several 8,000-pound Japanese Maple Trees among others, took<br />
them to a nursery and brought them back last spring and then planted<br />
them in exactly the same location as be<strong>for</strong>e.<br />
Q: What were some of the challenges you encountered with your<br />
design of the green roof on Vancouver’s Library Square Building?<br />
A: I don’t work with soils, so I knew already in 1976 I knew that I could<br />
only have a lightweight growing medium <strong>for</strong> the roofs <strong>for</strong> the Robson<br />
Square installation. So <strong>for</strong> the Library Square, I researched at great<br />
length how could I get a lightweight growing media and I came upon<br />
the idea to collect all the vegetable food waste from the restaurants in<br />
Vancouver and have them process it into compost. The final mix is<br />
one-third compost from vegetable food waste, one-third pumice and<br />
one-third sand: it’s called the Library mix — and we will use it at Robson<br />
Square again, so the challenge was to talk the owners into allowing<br />
us to use this lightweight material.<br />
“I feel that if you have chosen the profession<br />
of landscape architecture you have a duty to<br />
listen to what the times bring...I’ve always<br />
looked to the future.”
THEGROWINGMEDIA&PLANTISSUE<br />
Q: Looking ahead, what changes do you see?<br />
A: Well, first of all, we must curb this desire to sprawl. We must limit<br />
our footprints and employ the principles of ecodensity — that’s number<br />
one. Number two: we must use every bit of ground <strong>for</strong> public parks and<br />
not give it away to developers. Number three: if we want living buildings,<br />
we must work together as a team of architects, engineers, landscape<br />
architects.<br />
Q: As a landscape architect, how do you feel about the emergence of<br />
green walls?<br />
A: I think it is very good idea because they insulate the building against<br />
the cold and heat but they have to be built with drip irrigation. But I<br />
would like to speak to you about wildlife.<br />
Q: Please do...<br />
A: Well, we must build with a holistic approach, <strong>for</strong> example, it is important<br />
to include the Canada Geese, and all the other birds that flock<br />
around. Let them have fun on the roof!<br />
Q: Canada Geese on a roof?<br />
A: Yes. On the Library roof, I have two nice Canada Geese couples,<br />
(you know they mate <strong>for</strong> life), which come to certain balconies of the<br />
Court House, <strong>for</strong> instance, but the judges aren’t too happy with this<br />
and have asked <strong>for</strong> them to be removed — so I have not educated<br />
everyone yet! On the roof of the Vancouver Library, an inaccessible<br />
roof, I have two more sets of Canada Geese that sit on the roof and<br />
have their children and then they fly away and return every year. So<br />
education is necessary <strong>for</strong> a holistic approach that allows humans and<br />
geese to be part of the urban landscape.<br />
Q: If you could impart one kernel of wisdom to other professionals<br />
in this field, what would it be?<br />
A: Think about climate change which concerns all of us and what we<br />
have done to this planet. Learn what we can do and with every project<br />
to lessen the impact on the environment. <strong>Green</strong> roofs increase<br />
biomass, insulate buildings against heat and cold and slow down<br />
stormwater runoff, if they’re constructed properly. You can do this<br />
only if you have done your research and if you are working with<br />
professionals who know how to implement these ideas with working<br />
drawings and specifications.<br />
Q: A perfect ending — thank you <strong>for</strong> your wonderful visions and work. <br />
Caroline Nolan is the editor of the <strong>Living</strong> <strong>Architecture</strong> <strong>Monitor</strong>.
PROJECT<br />
ISLANDP<br />
<br />
LIVING ARCHITECTURE MONITOR<br />
WINTER
THEGROWINGMEDIA&PLANTISSUE<br />
PROJECTSPECIFICATIONS<br />
LOCATION Thousand Islands, Ontario<br />
PROJECTTYPE New Construction<br />
GREENROOFSIZE 1,700 square feet<br />
COMPLETIONDATE 2002-2003<br />
YEAROFAWARD 2004<br />
CLIENT/DEVELOPER Carol and Kevin Reilly<br />
ARCHITECT Shim-Sutcliffe Architects (Winner)<br />
DESIGNCONSULTANT Mill & Ross Architects<br />
DESIGNCONSULTANT Donald Chong Studio<br />
STRUCTURALENGINEERSBlackwell Engineering<br />
MECHANICALENGINEERSToews Systems Design (Mechanical)<br />
CONTRACTOR Michael Sheedy and Mark Peabody<br />
GREENROOFDESIGNER Marie-Ann Boivin, Soprema Canada<br />
GREENROOFLANDSCAPECONTRACTOR Top Nature, Montreal<br />
ARADISE<br />
By Flavia Bertram<br />
LIVING ARCHITECTURE MONITOR WINTER
PROJECT<br />
The majority of green roof projects are located in highly developed<br />
areas, characterized by limited green space, a searing urban heat<br />
island effect, stormwater management issues, and as such, often used<br />
to mitigate these negative effects of urbanization. Not so in the case<br />
of the 2004 Award of Excellence winning Howe Island home on the<br />
St. Lawrence River in the Thousand Islands, Ontario.<br />
The once rural, now semi-suburban island has a history of dairy farming<br />
and is not subject to the same environmental problems as city<br />
centers. As a result this green roof project was driven by aesthetics<br />
rather than the environmental benefits of the technology.<br />
Shim-Sutcliffe Architects conceived the house with the intent of<br />
The upper semi-intensive roof transposed the meadow plants from<br />
the ground to the roof, thereby integrating the building with the<br />
landscape. This visual effect is facilitated by the omission of parapet<br />
walls, resulting in roof perimeter details like those usually found<br />
on sloped rather than flat roofs. Six-inch deep growing medium sits<br />
on top of a modified bitumen membrane and root repellent layer<br />
and is contained by borders, which are then surrounded by stone<br />
vegetation-free zones to prevent the occurrence of plant erosion.<br />
Prior to construction, and to reinvigorate the large meadow, the<br />
five-acre site was hydroseeded (a process where a slurry of seeds<br />
and mulch is sprayed over a targeted area) with clover and a mixture<br />
of local indigenous flowers. The clover was harvested and<br />
respecting the region’s agrarian tradition and maintaining the openness<br />
of the landscape while providing their clients with privacy and a<br />
splendid view of the river. The green roofs, designed with Soprema<br />
Canada, were one of many elements that contributed the project<br />
goals of balancing the landscape, structure and water. On the side<br />
facing the St. Lawrence River the house opens up to a large water<br />
garden with indigenous water lilies and bulrushes.<br />
Initially, the two roofs did not utilize the same vegetation. The<br />
lower extensive roof was planted with a more traditional sedum<br />
palette, including Sedum album, Sedum floriferum ‘Weihenstephaner<br />
Gold’, Sedum kamtschaticum ellacombianum and Sedum<br />
Spectabile ‘Brilliant’.<br />
“The green roof is part of<br />
larger vision <strong>for</strong> landscape;<br />
it is one part of a greater<br />
approach to the agrarian<br />
context of the island.”<br />
Brigitte Shim, Shim-Sutcliffe Architects<br />
<br />
LIVING ARCHITECTURE MONITOR<br />
WINTER
THEGROWINGMEDIA&PLANTISSUE<br />
trans<strong>for</strong>med into bales of hay by a local farmer, continuing the<br />
site’s tradition of contributing to local agriculture.<br />
This same blend was subsequently used in the field of the upper<br />
roof of this island paradise, which was then bordered by sedums.<br />
This connection between the roof and the ground, however, proved<br />
to be problematic <strong>for</strong> the semi-intensive roof’s maintenance. The<br />
original plant-selection (comprised of French hybrids) were quickly<br />
overrun by native Canadian weeds and wildflowers. Though the area<br />
was reseeded after the establishment period was complete, the<br />
maintenance was certainly more than the client had bargained <strong>for</strong>.<br />
During the design phase, it became apparent to both the architects<br />
Both roofs have been annually supplemented with two or three flats<br />
of sedum to ensure continuous plant coverage.<br />
Despite this alteration, the striking Howe Island green roof continues<br />
to be an example of site-specific design that is sensitive to the visual<br />
and cultural aspects of the surrounding environment. The clover<br />
meadow and the two green roofs compliment each other, blurring the<br />
borders of the building roof and the ground plane. <br />
Flavia Bertram is a research assistant with <strong>Green</strong> <strong>Roofs</strong> <strong>for</strong> <strong>Healthy</strong> <strong>Cities</strong> in<br />
Toronto. She is also a contributor to a new book published by <strong>Green</strong> <strong>Roofs</strong><br />
<strong>for</strong> <strong>Healthy</strong> <strong>Cities</strong> and Schiffer Publishing called Stretching the Boundaries<br />
of <strong>Green</strong> Roof Design and <strong>Living</strong> <strong>Architecture</strong>: Five Years of Award-Winning<br />
“Once we<br />
got the right<br />
plants on<br />
the roof it<br />
became easy<br />
to handle.”<br />
Carol Riley, owner & client<br />
and manufacturer that the several-hours-by-car distances from the<br />
nearest centers of green roof knowledge in Canada —Toronto and<br />
Montreal — were too far <strong>for</strong> maintenance personnel to travel. As a result,<br />
the owners and a local gardener were trained in basic maintenance<br />
procedures and bore the responsibility <strong>for</strong> them. This capacity<br />
development is in keeping with the projects goals of respecting the island<br />
and surrounding area’s existing tradition of agrarian self-reliance.<br />
However, this independence also necessitated that the labour required<br />
in its upkeep be limited and resulted in the replanting of the<br />
upper roof with low maintenance drought resistant sedum species.<br />
Similarly, plants on the lower roof were redistributed after the establishment<br />
period was over in order to create a stronger plant palette.<br />
Projects in the spring. In the book other <strong>Green</strong> Roof Awards of Excellence<br />
winning projects and individuals are recognized <strong>for</strong> demonstrating extraordinary<br />
leadership and are celebrated <strong>for</strong> their valuable contribution to the<br />
green roof industry. This case study is but one of many featured in this exciting<br />
book, which will be launched at the upcoming annual GRHC conference<br />
in Baltimore in April. Please see www.greenroofs.org <strong>for</strong> details.<br />
INTERESTEDINHAVINGYOURPROJECTPROFILEDHERE?<br />
We are currently seeking excellent and innovative green roof and green<br />
wall projects <strong>for</strong> in-depth case studies <strong>for</strong> future “Project” consideration.<br />
Tell us about yours by sending an email to editor@greenroofs.org.<br />
It would be helpful to include a few photographs.<br />
LIVING ARCHITECTURE MONITOR WINTER
BESTPRACTICE<br />
THEORGANIC<br />
QUESTION<br />
WHENITCOMESTOGROWINGMEDIATHEREISCONSID-<br />
ERABLEDEBATEASTOWHATEXACTLYCONSTITUTESTHE<br />
BESTMIXFORSUPERIORPERFORMANCE<br />
On any green roof project, there inevitably comes a time when<br />
professionals must answer a crucial question: Exactly what kind of<br />
growing media is best <strong>for</strong> the roof’s long-term per<strong>for</strong>mance?<br />
In North America, much research is still required to determine the<br />
optimal composition of growing media and a wide variety of opinions.<br />
Currently, many green roof professionals are grappling with<br />
the issue of organics versus non-organic materials in growing media.<br />
Here, we present just two of those opinions from two, respected<br />
industry professionals, both members of <strong>Green</strong> <strong>Roofs</strong> <strong>for</strong> <strong>Healthy</strong><br />
<strong>Cities</strong>’ Growing Media Sub-Committee which is developing per<strong>for</strong>mance<br />
standards <strong>for</strong> growing media: Chuck Friedrich and Rick Buist.<br />
Rick Buist is a horticulturalist and president of BioRoof Systems<br />
Inc. and chair of the GRHC Growing Media Sub-Committee.<br />
Chuck Friedrich is also a horticulturist — and landscape architect —<br />
and is the director of horticulture research and product development<br />
<strong>for</strong> Carolina Stalite Company in Salisbury, North Carolina. He is<br />
also a member of the American Society of Landscape Architects, NC<br />
Landscape Contractors Association, and ASTM <strong>Green</strong> Roof Subcommittee.<br />
He also sits on the ASTM <strong>Green</strong> Roof Task Committee.<br />
<br />
LIVING ARCHITECTURE MONITOR<br />
WINTER
THEGROWINGMEDIA&PLANTISSUE<br />
“DON’TCALLITDIRT!”<br />
By Chuck Friedrich, RLA, ASLA<br />
My college soil science professor always reprimanded the class<br />
<strong>for</strong> referring to soil as “dirt.” He would always say: “dirt is<br />
something that is tracked in onto the carpet.” Actually the ideal<br />
green roof growing media should NOT contain any natural soil;<br />
there<strong>for</strong>e, we should not even call it soil. Most green roof professionals<br />
prefer the term growing media or medium, substrate, or<br />
planting media. My definition <strong>for</strong> green roof media is: “the particulate<br />
matter or substrate that anchors the plant roots to sustain plant<br />
growth.” Sounds simple, but it can get very complicated.<br />
For proper terminology, we should refer to the growing media as<br />
intensive or extensive green roof media. The media should be designed<br />
<strong>for</strong> the physiology of the plant material growing in the media.<br />
Sedums require an extensive media that has a coarser gradation than<br />
those used <strong>for</strong> grasses or other non-succulents. In addition to plant<br />
material, other factors affecting media selection are climate, weight,<br />
fertility, depth, location, microclimate, and irrigation. With all these<br />
factors to contend with we can then add a bunch of engineers to the<br />
equation. Over the past 15 years I have supplied green roof media on<br />
over 140 green roofs. It has been a learning experience offering much<br />
success. (Having a German last name didn’t hurt.)<br />
LOSINGORGANICMEDIA<br />
Trees, shrubs, lawns and flowers need water, air, space <strong>for</strong> the roots,<br />
and nutrients. Within the proper microclimate, many plants can<br />
grow better on the roof than on the ground. Why? With a green roof<br />
we can create a very big pot filled with the perfect growing media<br />
that is fertilized, irrigated, and most important, well drained. What<br />
we don’t want is a natural soil or a 100 per cent organic mixture<br />
GOINGFORORGANICS<br />
By Rick Buist<br />
When considering the writing of this best-practices article on<br />
using organics in growing medium, I reflected on the experiences<br />
I have had in the green roof marketplace to date. Since first becoming<br />
aware of the green roof industry, I had numerous people tell<br />
me how you shouldn’t use more than a certain percentage of organics<br />
in the growing medium. One says five per cent, another 20 per cent,<br />
and yet others argue it would be best if there were no organics at all!<br />
Now at the time, I found this all rather odd. Our company has many<br />
successful installations (over 80 to date) with few observed problems,<br />
and our sister company has been producing millions of cubic meters of<br />
organic-based growing mediums <strong>for</strong> decades to the nursery industry.<br />
Then I was told that our organic growing medium projects we installed<br />
did not have a long enough track record to be sufficiently evaluated.<br />
“Just you wait,” they ominously warned, ‘eventually the organic growing<br />
medium will disappear — it’ll be a disaster.” One person even<br />
claimed they had pictures of a green roof we installed showing exposed<br />
roots — impending doom was just around the corner!<br />
So I took all of this great advice to heart and also personally visited the<br />
site in question, only to discover the growing medium depth had not<br />
changed in four years. The roots were not exposed (although clumping<br />
fescues could give that appearance) and the owners were very happy.<br />
Naturally I had to ask myself: Why the strident accusations against organics<br />
in growing mediums?” Is it because some have invested in proprietary<br />
products associated with growing mediums? Is it because of the European<br />
experience? Or do they really have a sound scientific argument?<br />
LIVING ARCHITECTURE MONITOR WINTER
BESTPRACTICE<br />
contained up on a giant frying pan in the sky. Natural soils are<br />
cohesive and can change over a long period of time or simply get<br />
“damaged” if installed when wet. The same is true with organic<br />
matter; though it is a very important component, too much organic<br />
can be problematic depending on the circumstances.<br />
Organic matter breaks down and is washed out of the system due to<br />
rain or irrigation; to replace lost material could require many trips<br />
with heavy bags up steps or an elevator. The use of natural soil or too<br />
much of the wrong type of organic amendment may produce finer<br />
particles. Fine particles can move down and accumulate on the filter<br />
fabric, slowing down drainage. I have not been a big fan of sewage<br />
sludge compost <strong>for</strong> this reason. Runoff from green roofs containing<br />
levels of nutrients is a topic of current discussion with water quality<br />
researchers.<br />
The best practice is to use a media that will provide enough air<br />
throughout the profile to promote the roots to go down instead of<br />
up. If the bulk of roots are down deeper in the media where it is<br />
cool and moist, the better the plant can sustain itself during periods<br />
of extreme temperature.<br />
When proportionally blended, a mixture of lightweight aggregate,<br />
quality sand and organic compost makes a good media <strong>for</strong> intensive<br />
green roofs. 3/8" and finer lightweight aggregate has pore spaces in<br />
Throughout the horticultural and landscape industry, organics are the<br />
overwhelming trend. The industry has embraced organics’ role in sustaining<br />
biological functions in the soil. Research is abundant, covering<br />
actinomycetes, nematodes, micchorhizal fungi and various other microand<br />
macro-organisms (let’s not <strong>for</strong>get the lowly earthworm) — all of<br />
which bind contaminants, cycle nutrients, suppress disease and more.<br />
So once again, I asked myself: With this track record and research going<br />
on, why are many in the green roof world so opposed to using organics?<br />
If I were to ignore the obvious implications <strong>for</strong> those who have<br />
invested in distribution rights <strong>for</strong> European based systems, I would<br />
have to turn to the science behind the German Standards developed<br />
by the nonprofit known as Forschungsgesellschaft Landschaftsentwicklung<br />
Landschaftsbau (or FLL). I spent considerable time reviewing the<br />
FLL Standard and the research that led to its’ very conclusions.<br />
I also considered it imperative to understand the initial terms of reference<br />
and historical context by which the need <strong>for</strong> the standards<br />
came about. The terms of reference weighed very heavily on avoidance<br />
of problems, which given some of the failures in the German<br />
marketplace at the time, seemed to make sense. Un<strong>for</strong>tunately, I do<br />
not have enough article space to get into everything that I found;<br />
however, there are some serious holes.<br />
The first of which is the way the Standard does not adequately<br />
distinguish between organics (this may be because the science of soil<br />
biology was out of fashion at the time, research focused instead on<br />
the science of chemistry — much better funding opportunities).<br />
When referring to organics, there must be awareness that there is a<br />
huge array of source stock, composting processes, characteristics,<br />
etc…which makes it impossible to generalize. No one would suggest<br />
that we should refer to the entire automotive world as being all the<br />
same. Is a skateboard the same as an F1 racing car? That’s absurd. It is
THEGROWINGMEDIA&PLANTISSUE<br />
“Organic matter breaks<br />
down and goes away; to<br />
replace lost material could<br />
require many trips with<br />
heavy bags up steps or<br />
an elevator.”<br />
Chuck Friedrich<br />
the particles which lighten the load, retain nutrients and water, and<br />
best of all it is permanent. A good quality graded sand as filler is<br />
good <strong>for</strong> stability, and a measured amount of the proper organic<br />
compost provides microbial activity that is beneficial to the biology<br />
of the media. Currently, there are no standards related to the use of<br />
compost on green roofs.<br />
What about fertilizer? Save it <strong>for</strong> planting time. There is absolutely<br />
no reason to add fertilizer to a green roof media during the blending<br />
process. For good reason, in most cases the media is installed<br />
months be<strong>for</strong>e the first plant is installed. There<strong>for</strong>e, why spend<br />
money on fertilizer that will only end up leaching out and down the<br />
drain be<strong>for</strong>e the plants show up on the job? The best method is to<br />
blend a good slow release fertilizer into the top layer of the media<br />
during the planting operation.<br />
Once planted, provide lots of maintenance and irrigation; with that<br />
it can be beautiful and last <strong>for</strong> several decades. I <strong>for</strong>got to mention,<br />
also add lots of money, you get what you pay <strong>for</strong>. If you can keep the<br />
general contractor and schedule in check, the process can actually<br />
go smooth, right? Wrong. Don’t <strong>for</strong>get about the engineer.<br />
AWEIGHTYSUBJECT<br />
I am amazed how the specification on the weight of the media can<br />
be so tight, while in the same specification, the plan calls <strong>for</strong> 14<br />
Oak trees to be planted. It tickles me when I am asked at least<br />
twice per month by designers, “how much does a full grown tree<br />
weigh?” What? Dogwood or Sequoia? Does an additional pound or<br />
two per cubic foot of media, one way or another, make that much<br />
of a difference? I guess it will when 350-pound Aunt Bertha and<br />
the twins decide to have lunch up on the roof.<br />
All kidding aside, weight is an issue, especially on retrofitted extensive<br />
roofs. It is important to design using the saturated weight of the<br />
media. The ASTM Sub-committee <strong>for</strong> <strong>Green</strong> <strong>Roofs</strong> has developed<br />
standards <strong>for</strong> the practice and test methods <strong>for</strong> the determination<br />
almost as absurd to consider all organics to be the same. There are<br />
some organics that I would never use on a green roof (some of which<br />
were used in the research behind the FLL Standard). From cellular<br />
structure to composting process and beyond, organics are far too complex<br />
to generalize within a Standard.<br />
Secondly, the FLL Standard dictates organic content by mass. I can<br />
understand why, since the dominant testing method <strong>for</strong> organic content<br />
is the burn method, which can only measure by mass. However, by doing<br />
so, the Standard leaves a lot open to interpretation. For instance, one<br />
can use an extremely heavy inorganic material to achieve a high percentage<br />
of organic content since organics are generally much lighter. I was<br />
able to achieve organic content of over 60 per cent by volume in the<br />
growing medium but only eight per cent by mass. Was this ambiguity<br />
intended by the Standard?<br />
Interestingly, contrary to what I heard in the industry, the FLL Standard<br />
did allow <strong>for</strong> higher levels of organics. Section 9.2.2 states: “A greater<br />
proportion of organic matter may be required where special <strong>for</strong>ms of<br />
vegetation, such as humus rooting plants, are used.” This shows the<br />
importance of matching the growing medium to the physiological<br />
needs of the plants, another area largely uninitiated by many suppliers<br />
in our industry.<br />
Thirdly, the Standard focused on material specifications instead of<br />
per<strong>for</strong>mance specifications and by doing so, essentially closed the<br />
door on innovation. (It seems the lowly sedum is the order of the day,<br />
matched to equally low per<strong>for</strong>mance mediums). This caused companies<br />
to scramble to find similar products in North America with the<br />
prize going to those who could quickly identify and corner the market<br />
on certain products. As most of the construction industry in North<br />
America makes the change to per<strong>for</strong>mance-based specifications, the<br />
FLL Standard represents a step backward.<br />
Lastly, I concluded the Standard itself was not as much a problem<br />
as people’s interpretation of it. For example; there seems to be much<br />
misunderstanding of what organic content is. One hundred per cent<br />
FORMULATING, TESTING, PLANT<br />
GROWTH TRIALS, PROBLEM SOLVING<br />
“SEND US YOUR<br />
EXTENSIVE/INTENSIVE 5<br />
GALLON PAIL PLEASE!”<br />
SOIL CONTROL LAB<br />
42 HANGAR WAY<br />
WATSONVILLE, CA 95076<br />
(831) 724-5422 PHONE,<br />
(831) 724-3188 FAX,<br />
WWW.GREENROOFLAB.COM<br />
FRANK@COMPOSTLAB.COM<br />
CONTACT: FRANK SHIELDS
“Why the strident<br />
accusations against<br />
organics in growing<br />
mediums? Is it because<br />
some have invested in<br />
proprietary products<br />
associated with growing<br />
mediums? Is it because<br />
of the European experience?<br />
Or do they really<br />
have a sound scientific<br />
argument?”<br />
Rick Buist<br />
organic material may only have an end organic content of 20 per cent.<br />
The remaining 80 per cent may be inorganic or mineral based. This is<br />
largely lost in the language of the industry.<br />
The per<strong>for</strong>mance which organic matter brings to stormwater retention,<br />
pollutant degradation, plant variety, cooling benefits, sustainable materials,<br />
etc. is too great to ignore.<br />
Organic-based growing media can hold far more water than mineralbased<br />
growing mediums while maintaining porosity; this is because of<br />
the way in which they hold water through particle swelling instead of just<br />
void filling and capillary <strong>for</strong>ces. Biology can be customized to degrade
THEGROWINGMEDIA&PLANTISSUE<br />
of dead loads and live loads associated with green roof systems. If<br />
flooded, the media weight could increase up to 20 pounds over the<br />
drained weight. This could be catastrophic when a heavy snow load<br />
is added to roof during the same event.<br />
MEDIAFORSEDUMS<br />
Most extensive growing media is used in a thin profile of three to six<br />
inches. If weight restrictions allow; go deeper, just keep Aunt Bertha<br />
off the roof.<br />
Sedums do well in aerated media. Most extensive media is at least<br />
80 per cent lightweight aggregate (<strong>for</strong> porosity and nutrient retention).<br />
Care must be taken not to design a growing media that is too<br />
fine. If the media does not routinely dry out, excessive water may<br />
cause weed promotion and some sedum roots to rot.<br />
Sedums will die quicker if the media stays too wet rather than<br />
too dry. In my view, it is better to provide a well-drained material<br />
with supplemental irrigation then to have plant loss during the<br />
rainy season.<br />
SPEAKINGOFIRRIGATION<br />
Those who think extensive green roof systems do not need, at least<br />
temporary irrigation ought to camp out on a green roof in North<br />
Carolina during an August heat wave. I have run several studies in<br />
NC and have been able to just get by without automatic watering.<br />
That success ended with this year’s record drought. No matter how<br />
fine the media was or the amount of organic content in the mix, the<br />
sedums still died from lack of moisture. Without the morning mist<br />
experienced daily in Germany and the Pacific Northwest, sedums<br />
have a tough time in hotter and drier climates. Though sedums may<br />
go dormant and survive a green roof that looks like dead weeds is<br />
bad <strong>for</strong> business. Find a water source, reclaimed if you must, and<br />
find a way to get it up on the roof. Do not over water; monitoring irrigation<br />
after the establishment period is essential. The controversy<br />
over irrigation will continue; occasional drip irrigation as needed<br />
works. The holdouts need to quit bellyaching and just do it.<br />
In conclusion, controversy between schools of thought over green<br />
roof media will continue within the United States. Being in its infancy<br />
compared to Europe, whether intensive or extensive, communications<br />
between the parties involved do tend to drift. When everyone<br />
with professional integrity and the proper knowledge work together<br />
and stay current with the latest technology, the long-term results will<br />
benefit everyone. <br />
specific and non-specific pollutants. Plants that provide evaporative<br />
cooling can be used more frequently with success. Fertilization can<br />
occur naturally through nutrient cycling. Materials can be sourced<br />
locally. And the list of benefits goes on.<br />
Practically every argument I have heard against the use of organics<br />
comes with a relatively easy solution:<br />
• Lost depth because of organic cycling is easily addressed through<br />
inputs such as biomass created by the plant choice through roots<br />
or refuse, or annual (if required at all) top-dressing with a<br />
pelletized product such as compost or alfalfa (readily available<br />
in dry, bagged <strong>for</strong>m).<br />
• Fines clogging drains or water-logging can be averted by careful<br />
selection of organic materials. Organics with crystalline structures,<br />
such as certain bark-based products, will behave much like sand <strong>for</strong><br />
free drainage, while organics with strand characteristics will hold<br />
structure together. Careful selection and installation of components<br />
such as filter cloth are also helpful.<br />
• Wind erosion is averted by using biodegradable netting until plants<br />
are established, thereby providing continuous cover.<br />
• Fire prevention can be improved by avoiding certain substances<br />
(i.e. peat moss — a limited resource) and by using organics with<br />
high ignition-thresholds and large moisture-retention capacities.<br />
Although any biomass on a roof can burn, it is easy to mitigate the<br />
risk by paying attention to the details.<br />
My intention in promoting the use of organics is not to replace<br />
the good work already achieved by the FLL Standard (the bulk of<br />
which I strongly endorse), but to expand its terms of reference. We<br />
should not be afraid of opening the door to creativity. Let’s set<br />
per<strong>for</strong>mance objectives that will not only serve to reduce risk but<br />
also allow <strong>for</strong> innovation.<br />
We should also practice what we preach. If we as an industry are<br />
promoting stormwater retention or cooling benefits, we must prescribe<br />
a high level of per<strong>for</strong>mance to justify the cost of our product. If<br />
not, we risk being passed off as a fad, as eco-chic. Are we environmental<br />
stewards? Don’t we appear hypocritical by using mined products<br />
<strong>for</strong> the bulk of our material? If we’re pushing the idea of biodiversity,<br />
we must use plantings that give entomological teeth to our argument.<br />
An immature marketplace is always better served by collaboration<br />
than by competition. We risk alienating an extremely large demographic<br />
in the landscape, horticultural and composting industries who<br />
could help our industry immensely if we continue to promote against<br />
the use of organics. <br />
LIVING ARCHITECTURE MONITOR WINTER
NATIVEPLANTRESEARCH<br />
IMPACTOFGROWINGMEDIA<br />
ON PRAIRIEGRASSES<br />
RESEARCHFROMLINCOLNNEBRASKAPROVIDESINSIGHTONTHEPERFORMANCEOF<br />
GROWINGMEDIAINTHEESTABLISHMENTOFTALLNATIVEGRASSESONEXTENSIVEROOFS<br />
By Richard K. Sutton<br />
American conservationist, Aldo Leopold asked us to “Think like a<br />
mountain.” When it comes to extensive green roofs in drier climates,<br />
however, we need to think like a prairie.<br />
Selected research on tall grass prairie species questions their use,<br />
but sedum now used on too many extensive green roofs is a monoculture<br />
inherited from Northwest European countries including<br />
Germany — and nature rewards diversity.<br />
In the Great Plains’ climate, short- and mid-grass prairies have<br />
evolved diverse communities of grasses, <strong>for</strong>bs and sedges in shallow<br />
soil with hot summers, cold winters, high winds, low humidity<br />
and little rainfall. While sedum grows well in Germany’s effective 15<br />
to 18 inches of net precipitation (accounting <strong>for</strong> potential evapotranspiration),<br />
the Great Plains prairie can flourish on net precipitation<br />
that has a 0- to 15-inch deficit.<br />
Thinking like a prairie in 2006, Architectural Partnership, an architectural<br />
firm in Lincoln, Nebraska, designed the state’s first public<br />
building, the Pioneers Park Nature Center (PPNC) Prairie Building<br />
addition, to incorporate a 900-square-foot extensive green roof.<br />
The green roof uses Hydro-tek Gardendrain system covered by<br />
three and one-half inches of Rooflite’s 95 per cent heat expanded<br />
shale and five per cent compost by volume.<br />
Given where the building was situated, it was only logical to take<br />
note of the mission of the Pioneers Park Nature Center (PPNC) —<br />
that is, to teach the public about the importance of native plants<br />
and animals — and use prairie plants on the green roof.<br />
As a landscape architect doing research at UN-Lincoln, I worked<br />
with the PPNC staff to design an assemblage of green roof prairie<br />
plants that included grasses, sedges and <strong>for</strong>bs. Plantings were<br />
placed to be ongoing three- to five-year (or longer) experimental<br />
plots and a roof-top prairie.<br />
Our first studies look at the establishment of the selected prairie<br />
plants especially their growth under two simple treatment additions<br />
to the Rooflite media.<br />
Though the first treatment (supplementing available moisture with<br />
super-absorbent polymer gels such as Horta-sorb) has been<br />
around the horticulture industry <strong>for</strong> years it has not, to my knowledge,<br />
yet found its’ way onto green roofs.<br />
The second treatment (adding soil microbes gleaned from prairie<br />
soils) has gained use in landscape plantings on low-nutrients soils and<br />
hypothesized to help activate the compost fraction in the media, thus<br />
making nutrients and water more readily available to plants.<br />
A dozen six-by-six foot plots were randomly planted eight inches on<br />
center to a mixture of native species consisting of six grasses, one<br />
sedge and five <strong>for</strong>bs as # 72 plugs. Three plots each were randomly<br />
assigned to:<br />
“American conservationist, Aldo<br />
Leopold asked us to ‘Think like<br />
a mountain.’ When it comes to<br />
extensive green roofs in drier<br />
climates, however, we need to<br />
think like a prairie.”<br />
LEFTBecky Seth, a Pioneers Park Nature Center naturalist, assists Dr.<br />
Richard Sutton in recording prairie plant growth ratings on the nature<br />
center’s new extensive green roof.
FIRSTGROWINGSEASONPLOTGROWTHRATINGSFOR<br />
TREATMENTSWITHMICROBESHORTA-SORBHEIR<br />
INTERACTIONANDROOFLITECONTROL<br />
GROWTHRATINGSANDAVERAGEFORTREATMENTS<br />
TREATMENTS TOTALPERBLOCK AVERAGETREATMENT AVERAGEPERPLANT<br />
GROWTHRATING GROWTHRATING GROWTHRATING<br />
Blk 4 A Control 169<br />
Blk 7 A Control 153<br />
Blk 20 A Control 152<br />
474 158 2.63<br />
Blk 1 B Microbes 168<br />
Blk 3 B Microbes 167<br />
Blk 5 B Microbes 168<br />
503 168 2.80<br />
Blk 6 C Horta-Sorb 183<br />
Blk 10 C Horta-Sorb 182<br />
Blk 11 C Horta-Sorb 176<br />
541 180 3.00<br />
Blk 2 D Microbes + Horta-Sorb 202<br />
Blk 8 D Microbes + Horta-Sorb 192<br />
Blk 9 D Microbes + Horta-Sorb 188<br />
582 194 3.23<br />
1) A treatment of: Horta-sorb;<br />
2) A slurry of prairie microbes;<br />
3) A combination of Horta-sorb and microbes; and<br />
4) A control consisting of straight Rooflite.<br />
6 = Roots well established and exceptional growth and vigor and establishment<br />
of plant crown greater than 6 cm but less than 10 cm;<br />
7 = Plant expanding beyond 10 cm but less than 16 cm; and<br />
8 = Plant expanding to greater than 16 cm.<br />
In addition, 95-hundredths of an inch of water was applied by irrigation<br />
per week from June to September.<br />
The plants were examined monthly from July to October and rated <strong>for</strong><br />
growth and establishment, using the following system:<br />
PLANTGROWTHRATINGSYSTEM<br />
0 =Dead or missing plant;<br />
1= Live plant in poor condition; less crown or stem growth than when<br />
planted plant loose; no rooting beyond initial plug;<br />
2 = Plant established but crown not expanding or top growth stagnant,<br />
beyond areas of plug;<br />
3 = Plant with roots established and crown expanding up to 1 cm<br />
beyond; or vigorous top growth;<br />
4 = Plant roots established and plant crown expanded up to 2 cm<br />
beyond; additional stems;<br />
5 = Roots well established and vigorous; plant crown expanded beyond<br />
original plug area by greater than 2 cm but less than 6 cm;<br />
Data from the end of the first growing season (October) is just being<br />
analyzed. Raw plot totals <strong>for</strong> plant growth ratings are greatest (above)<br />
<strong>for</strong> the interaction of Horta-Sorb and the slurry of microbes, next<br />
<strong>for</strong> the Horta-Sorb alone, then next <strong>for</strong> the slurry of microbes alone<br />
and finally lowest <strong>for</strong> the Rooflite media alone. This data has not<br />
been checked <strong>for</strong> homogeneity of variance or significant differences,<br />
however the visual difference between the treatments and the control<br />
are readily apparent when one sees the green roof plots <strong>for</strong> the<br />
plants in treatments are greener and appear more robust. The implications<br />
are that media manipulation may make short and mid-grass<br />
prairie plantings a viable alternative to sedum <strong>for</strong> extensive green<br />
roofs in the Great Plains. <br />
Richard K. Sutton, ASLA, Ph.D, is a Lincoln, Nebraska-based associate<br />
professor of Agronomy and Horticulture and Horticulture and Landscape<br />
<strong>Architecture</strong> at the University of Nebraska-Lincoln. He is a<br />
featured presenter at <strong>Green</strong> <strong>Roofs</strong> For <strong>Healthy</strong> <strong>Cities</strong>’ upcoming annual<br />
conference — www.greenroofs.org/baltimore.<br />
LIVING ARCHITECTURE MONITOR WINTER
NATIVEPLANTRESEARCH<br />
NATIVESURVIVORS<br />
Ron Wik<br />
THENEWENGLANDWILDFLOWERSOCIETYINPARTNERSHIPWITHTHEMASSACHUSETTS<br />
COLLEGEOFARTISTRIALINGNATIVEPLANTSHEREISWHATTHEY’VELEARNEDSOFAR<br />
ABOUTCERTAINSUN-ANDDROUGHT-TOLERANTSPECIES<br />
By Ron M. Wik<br />
The use of native plant species on green roofs is a topic of<br />
increasing interest, especially in the Northeast where architects<br />
want to make buildings that are both “green” and sustainable.<br />
To meet that demand, designers are requesting a palette of plant<br />
material of North American origin. These installations can represent<br />
entire ecosystems by providing food sources and shelter <strong>for</strong><br />
birds and insects.<br />
Many North American indigenous plant species are suitable <strong>for</strong><br />
green roof installations. These are typically plants that have<br />
evolved in exposed areas, such as mountainous regions. Others<br />
originate in sandy or xeric conditions, where they have developed<br />
strategies to cope with lack of water. In both habitats, survival involves<br />
morphology devoted to water storage or reduction of water<br />
loss. Fleshy leaves and stems are especially useful <strong>for</strong> plants needing<br />
to cope with drought and high temperatures.<br />
New England Wild Flower Society has partnered with the Massachusetts<br />
College of Art to test the stamina of native plants on the 11th<br />
floor of a building in southwest Boston, Massachusetts. These<br />
sun- and drought-tolerant species were selected primarily from sand<br />
prairie and alpine biomes to cope with the site’s southern exposure<br />
and the sandy media (89 per cent sand; six to nine inches deep).<br />
The plants were watered twice weekly <strong>for</strong> one-month after planting,<br />
with no further irrigation since. The study began in October 2005.<br />
Antenarria parlinii ssp. fallax (Plantain Pussytoes) and A. rosea<br />
(Rosy Pussytoes) are both low growing (two to four inches) species,<br />
<br />
LIVING ARCHITECTURE MONITOR<br />
WINTER
THEGROWINGMEDIA&PLANTISSUE<br />
Ron Wik William Cullina William Cullina<br />
OPPOSITEPAGETest Site: The 11th floor MassArt <strong>Green</strong> Roof at Boston’s Massachusetts College of Art. The 1,000-square foot semi-intensive research roof has<br />
a one-per cent slope and was designed by Somerville, MA-based Heimarck & Foglia, LLC. LEFTAntenarria rosea (Rosy Pussytoes) CENTRESedum nevii (Nevius’<br />
Stonecrop) RIGHTSibbaldiopsis tridentata (Three-Toothed Cinquefoil)<br />
flowering in spring. The dense silver/grey foliage provides substantial<br />
textural interest and excellent coverage. Remarkably, we found<br />
a brood of painted lady butterfly larvae <strong>for</strong>aging in these plants —<br />
110 feet above ground level.<br />
Aster ericoides f. prostratus (Heath Aster) and A. spectabilis<br />
(Showy Aster) have had no difficulty flourishing in the xeric rooftop<br />
conditions. They establish quickly and extend the floral interest<br />
well into frost. A. ericoides is a prostrate species achieving a maximum<br />
height of six inches and <strong>for</strong>ming a dense mat covered in tiny<br />
white flowers from late July to October. A. spectabilis produces<br />
dense basal foliage with stalks reaching 18 inches and bearing large<br />
purple flowers.<br />
Houstonia caerulea (bluets) <strong>for</strong>m low (one inch) mats of tiny dark<br />
green leaves. Stalks of pale blue flowers, produced from spring<br />
until frost, reach four inches in height. This species reseeds readily<br />
and tends to wander around the planting area. It quickly fills in the<br />
nooks and crannies left by other establishing plants.<br />
Schizachyrium scoparium (Little Bluestem) is a grass species known<br />
<strong>for</strong> being extremely adaptable. It establishes very quickly, <strong>for</strong>ming<br />
tufts of silver/green foliage. Fuzzy purple inflorescences (18—24<br />
inches) are produced in the fall and persist through the winter.<br />
Sedum nevii (Nevius’ Stonecrop) is one of several North American<br />
stonecrops. It is especially drought-tolerant, producing a thick mat<br />
(three inches) of burgundy-tinged, mint green foliage. White flowers<br />
in early summer produce seed that speeds coverage.<br />
Sibbaldiopsis tridentata (Three-Toothed Cinquefoil) <strong>for</strong>ms an extremely<br />
dense mat (three to four inches) of shiny dark green leaves.<br />
It has proven to be especially resilient, colonizing rapidly and producing<br />
small white flowers sporadically throughout the summer.<br />
This is just a small selection of the species that have proven successful<br />
under these challenging conditions. All of them are showing<br />
excellent promise <strong>for</strong> lesser soil depths. New England Wild Flower<br />
Society will continue to assess native plants to promote the implementation<br />
of sustainable green roofs and intends to carry on this<br />
study indefinitely. <br />
Ron M. Wik, nursery business director, Nasami Farm Native Plant<br />
Nursery in Whately, MA. The nursery is operated by the New<br />
England Wild Flower Society, America’s oldest plant conservation<br />
group. Its botanical and horticultural living museum, Garden in<br />
the Woods in Framingham, Massachusetts displays 1,500 mature<br />
native plant species and cultivars including 200 rare species.<br />
www.newenglandwild.org.<br />
LIVING ARCHITECTURE MONITOR WINTER
EXTREMECONDITIONS<br />
HOTANDHUMID<br />
WHATPLANTSWORKBESTINTROPICALANDSUBTROPICALSITUATIONS?<br />
By Steve Skinner<br />
The vast majority of extensive green roofs in Europe and North<br />
America have been based on traditional plantings of sedums<br />
and other highly drought-tolerant plants on non-irrigated roofs in<br />
relatively mild climates. In the last few years, however, innovative<br />
designers have demonstrated that the benefits of extensive green<br />
roofs — including stormwater management, energy savings and<br />
bringing nature to the built environment — can be enjoyed in<br />
almost any climate.<br />
In North America, successful extensive green roofs have been<br />
established from Alaska to Mexico and from Nova Scotia to the<br />
Caribbean. To succeed in more extreme climates designers must<br />
recognize the limitations of traditional extensive green roofs<br />
and adjust plant choices, growing media and system build-up to<br />
account <strong>for</strong> the climate extremes that will be encountered.<br />
The hot and humid climates found in the tropics and subtropics, <strong>for</strong><br />
instance, simply will not sustain traditional green roof plants such as<br />
sedums. In these areas, daily precipitation with persistent high temperatures<br />
and humidity commonly occurs in the spring and summer.<br />
Alternately, during the fall and winter, extended periods of water<br />
deficits are not uncommon. Sedums and other traditional green roof<br />
plants cannot withstand the humidity and constant high temperatures<br />
in the summer in these areas and will likely perish.<br />
So what is necessary <strong>for</strong> extensive green roofs to succeed in tropical<br />
and subtropical areas? First, designers must select plants that can<br />
cope with the very wet and hot spring/summer conditions and then<br />
plan to irrigate during the extended drier periods in the fall and winter.<br />
Many native groundcovers and vines possess the ability to cope<br />
with constant heat and very wet conditions and yet survive with little<br />
extra water during dry periods. Many of these plants naturally occur<br />
in sandy coastal soils that are low in nutrients due to frequent leaching<br />
and have evolved shallow fibrous root systems that can anchor<br />
them during the frequent strong winds experienced in these areas.<br />
Plants such as Muhly Grass (Muhlenbergia, various species), Coral<br />
Honeysuckle (Lonicera sempervirens), Dune Sunflower (Helianthus<br />
debilis) and other associated species can thrive in as little as five to<br />
six inches of growing media, and once established, need supplemental<br />
water only during extended periods of drought.<br />
Secondly, <strong>for</strong> hot and humid climates, a growing media with the dual<br />
properties of a) good water holding and b) easy drainage of excess<br />
water, are even more critical than <strong>for</strong> most green roofs. The heat,<br />
<br />
LIVING ARCHITECTURE MONITOR<br />
WINTER
THRIVINGCONDITIONS<br />
Tips <strong>for</strong> sustaining growth on extensive green roofs in tropical and<br />
subtropical areas.<br />
• Select native plants that can cope with wet and hot spring/summer<br />
conditions.<br />
• Plan to irrigate during drier periods in the fall and winter.<br />
• Select plants from well-drained, sandy coastal environments that<br />
spread quickly.<br />
• Select low-growing species with fibrous root systems to<br />
withstand wind.<br />
• Use high-quality growing media with great water holding capacity<br />
that still drains well when saturated.<br />
Even the best possible plants will need a green roof system that can<br />
provide three critical elements to sustain growth.<br />
1. A method <strong>for</strong> keeping subsurface water in reserve that can be<br />
accessed when evapotranspiration exceeds available water in the<br />
growing media. This can be achieved efficiently with drainage mats<br />
with built in water reservoirs or with moisture mats.<br />
2. A means to provide good aeration even when the growing media<br />
is saturated.<br />
3. An excellent drainage capacity to deal with frequent intense<br />
rainfal events.<br />
THRIVINGCONDITIONSFORTHISEXTENSIVEROOFATPERRY<br />
YARDATTHEUNIVERSITYOFFLORIDA’SRINKERHALLINHOT<br />
ANDHUMIDGAINESVILLEFLORIDA<br />
Tropical and subtropical climates pose a challenge to green roof<br />
designers but thoughtful application of high quality systems can<br />
produce outstanding results.<br />
wind and high solar energy levels in these areas create very high<br />
evapotranspiration rates and the thin growing media of extensive<br />
roofs means that water delivery to the plants must be highly efficient.<br />
At the same time, intense rainfall requires a media that has<br />
high hydraulic conductivity to allow excess water to rapidly drain.<br />
“Many native groundcovers<br />
and vines possess the<br />
ability to cope with<br />
constant heat and very<br />
wet conditions and yet<br />
survive with little extra<br />
water during dry periods.”<br />
The third most critical criterion <strong>for</strong> success in hot and humid areas<br />
is to have a green roof system that provides the ability to retain<br />
water in reserve that can be accessed by the plant root systems<br />
when high evapotranspiration rates rapidly deplete the moisture in<br />
the growing media. A water reserve provided by drainage mats that<br />
have built-in water reservoirs and the use of moisture retention<br />
mats can reduce, but not eliminate, the need <strong>for</strong> supplemental<br />
irrigation when evapotranspiration exceeds precipitation.<br />
Recently, recognition and planning <strong>for</strong> the special set of<br />
conditions found in hot, wet climates in Florida (University of<br />
Florida in Gainesville, University of Central Florida in Orlando<br />
and the Nancy Foster Environmental Center in Key West), Texas<br />
(University of Houston) and on Necker Island, BVI (Virgin Resorts)<br />
have resulted in extensive green roofs that adhere to the principles<br />
of low weight, low maintenance and an aesthetically pleasing<br />
appearance that have fostered a booming green roof market in<br />
other parts of the world. <br />
Steve Skinner joined American Hydrotech, Inc. as garden roof product<br />
manager in 2003 after a 20-plus year career as a soil scientist<br />
and environmental manager. He has served on the board and in<br />
numerous committees with <strong>Green</strong> <strong>Roofs</strong> <strong>for</strong> <strong>Healthy</strong> <strong>Cities</strong> and on<br />
several green roof industry task groups.<br />
LIVING ARCHITECTURE MONITOR WINTER
EXTREMECONDITIONS<br />
COLD<br />
ATOUROFTHENORDICCOUNTRIESREVEALSATHRIVINGGREENROOFINDUSTRY<br />
By Kerry Ross<br />
In the summer of 2007 the Royal Architectural Institute of<br />
Canada sponsored a tour of Nordic green roofs through the<br />
Burwell Coon Travel Scholarship. For most of a month, my husband,<br />
Bob and I toured a variety of cold climate green roof projects<br />
where we photographed and documented different green roof<br />
solutions and met with a number of individuals involved in green<br />
roofing. The purpose of the study was to gain a better understanding<br />
of contemporary green roofs from northern regions where the<br />
technology was more advanced; areas which share climatic characteristics<br />
similar to regions of Canada such as long, cold winters,<br />
short growing seasons, extreme sun paths and reduced numbers of<br />
suitable plant species.<br />
The excursion included stops in Iceland, Denmark, Norway and Sweden.<br />
In many of the areas we visited, we found that while general<br />
awareness of green roof technology seemed surprisingly modest, we<br />
nevertheless discovered that there were both new traditional style<br />
green roofs as well as contemporary green roof applications.<br />
In Scandinavia, we were struck by how significant the influence of<br />
the Gulf stream on the climate and vegetation of the region even at<br />
the most northern latitudes of our visit (Selfoss, Iceland at 63.94° N<br />
and Trondheim, Norway at 63° 36’) both destinations several hundreds<br />
of kilometers north of my adopted hometown of Calgary (51° 6’<br />
N). We observed that many plant species, incapable of growing in<br />
Calgary, seem to grow vigorously in the Northern regions of Scandinavia.<br />
As we climbed in elevation and travelled inland, however, the<br />
effect of the Gulf Stream fell away.<br />
One of our stops included a visit to the Have og Landscab (Garden<br />
& Landscape) Expo in Slagelse, Denmark, an annual event held in<br />
August attracting hundreds of companies involved in the landscape<br />
industry from all over Scandinavia. It was there that I met representatives<br />
from Veg Tech AB, the largest green roof supplier in Scandinavia.<br />
While sedum mats are one of their best-selling systems,<br />
another that is particularly interesting consists of pre-grown “herb<br />
and sedum” mats that use a mixture of perennial grasses and flowering<br />
<strong>for</strong>bs and resembles a meadow or the <strong>for</strong>est floor. This product<br />
provides immediate coverage, excellent cold and drought hardiness<br />
as well as greater biodiversity.<br />
While in Denmark, I had a chance to see an installation of the<br />
herb and sedum mat on a rooftop of a new multi-family residential<br />
building in the emerging district of Ørestad in South Copenhagen.<br />
Historic urban housing in Copenhagen is characterized by four to six<br />
storey apartment blocks built around a common courtyard which are<br />
frequently used <strong>for</strong> gardening, barbecuing, outdoor play and picnics.<br />
With the urban renewal of the historic center, Copenhagen is going<br />
through a building boom. Along with a number of key cultural commissions,<br />
significant growth in the development of urban housing can<br />
be seen. This building boom is characterized by more varied housing<br />
stock and often larger scaled buildings. In place of the historical<br />
courtyard amenity, rooftop amenities including green roofs are<br />
starting to emerge. <br />
Kerry Ross is an architectural consultant with IBI Group Architects<br />
Engineers in Calgary, Alberta.<br />
LEFTPre-grown mats installed on upper roof deck of multi-family housing project. CENTRETOP <strong>Green</strong> wall on Reykavik City Hall<br />
CENTREBOTTOM<strong>Green</strong> roofs on Solheimar Ecovillage main hall in Selfoss, Iceland RIGHTPre-grown herb & sedum mats from Veg Tech AB in Scandinavia.
THEGROWINGMEDIA&PLANTISSUE<br />
DROUGHT<br />
EVALUATINGTHEPERFORMANCEOFGREENROOFPLANTSANDGROWINGMEDIUM<br />
By Dr. Bill Retzlaff, Dr. Susan Morgan, Kelly Luckett and Vic Jost<br />
Two of the most critical decisions facing those wishing to place<br />
a green roof are plant and growth media selections. Choose the<br />
wrong species mixture or the wrong growth-media <strong>for</strong>mulation and<br />
a failed green roof project will usually result.<br />
The <strong>Green</strong> Roof Environmental Evaluation Network (G.R.E.E.N.) at<br />
Southern Illinois University Edwardsville (SIUE) has evaluated 40+ plant<br />
species and more than a dozen growing mediums <strong>for</strong> use in extensive<br />
green roof systems since spring 2005. We have made a number of significant<br />
discoveries in these areas that have implications <strong>for</strong> the green<br />
roof industry — and this article highlights some of our initial discoveries.<br />
Some sedum species will not tolerate winter shade while others<br />
do quite well (See “Winter Shading” next page). In a fully replicated<br />
species/media/fertilizer experiment on the Engineering Building roof<br />
at SIUE, 100 per cent of Sedum hybridum immergrunchen was lost<br />
when the roof was in full winter shade (no direct sunlight) while other<br />
species, like S. sexangulare, experienced 100 per cent winter survival.<br />
Similarly, some sedum species will not tolerate heat-released fertilizers<br />
while others have no fertilizer preference (See “Heat & Release,”<br />
next page). Sedum floriferum ‘Weihenstephaner Gold’ suffered fertilizer<br />
injury from a commercial slow-release fertilizer following a minimal<br />
rainfall event while other species, like S. sichotense, experienced<br />
no injury. We now use and recommend a fertilizer blend of Osmocote-Nutricote-IBDU<br />
to avoid this injury issue.<br />
Unsurprisingly, mixed sedum plugs are a better option than monocultures<br />
of single sedum species (see “Biodiversity Works,” next page).<br />
We have lost many plant species due to heat, cold, fertilizer,<br />
drought, growth media over-saturation, and shading. The use of a<br />
single species in a green roof project and the loss of that species has<br />
resulted in green roof project failures. As a consequence, we are<br />
now evaluating mixed species plugs containing as many as five different<br />
sedums. The mixed species plugs were planted on our research<br />
green roof in <strong>Green</strong> Roof Blocks and <strong>Green</strong> Paks in March 2007.<br />
Plant growth and roof coverage are excellent at the end of the first<br />
growing season (November 2007).<br />
One recycled growing medium that we are evaluating consisting of 80<br />
per cent spun-glass aggregate and 20 per cent composted pine bark<br />
remains saturated even during periods of drought. While promising in<br />
that it retains high-moisture content, it stays too wet <strong>for</strong> sedum (see<br />
“Saturated <strong>Green</strong> Roof,” next page). The saturated root-zone reduces<br />
growth and results in plant losses. Because the moisture-holding capacity<br />
of growing mediums is critical, in the lab we determined the<br />
maximum moisture retention of various growth media blends, consisting<br />
of 20 per cent organic material and 80 per cent aggregate (see<br />
“20-80 Best” next page).<br />
Our results demonstrate that lava rock, a natural aggregate, has a<br />
similar moisture retention to Arkalyte, a heat-expanded aggregate<br />
“One recycled growing medium that<br />
we are evaluating consisting of 80<br />
per cent spun-glass aggregate and<br />
20 per cent composted pine bark<br />
remains saturated even during<br />
periods of drought.”<br />
LIVING ARCHITECTURE MONITOR WINTER
FIGURE//WINTERSHADING<br />
FIGURE//HEAT&RELEASE<br />
FIGURE//BIODIVERSITYWORKS<br />
FIGURE//SATURATEDGREENROOF<br />
FIGURE//-BEST
THEGROWINGMEDIA&PLANTISSUE<br />
LEFTFIGURE//WINTERSHADINGEffect of full, winter shading on survival of Sedum hybridum immergrunchen (left picture — no survival) and S. sexangulare<br />
(right picture — 100 per cent survival). FIGURE//HEAT&RELEASEEffect of fertilizer injury under low rainfall conditions on Sedum floriferum ‘Weihenstephaner<br />
Gold’ (left picture — foliage burning) and S. sichotense (right picture) FIGURE//BIODIVERSITYWORKSEvaluation of mixed species plugs in<br />
green roof applications — exceptional growth and roof coverage after one growing season. FIGURE//SATURATEDGREENROOFEffect of growth media<br />
water-holding capacity on per<strong>for</strong>mance of Sedum hybridum immergrunchen. On the left, 80 per cent spun-glass aggregate and 20 per cent composted pine bark.<br />
On the right, results with 80 per cent Arkalyte and 20 per cent composted pine bark. FIGURE//-BESTEvaluation of the per<strong>for</strong>mance of various commercially<br />
and specially blended growth media: lava, Arkalyte, bottom ash and Haydite, respectively.<br />
(32 vs. 30 per cent, respectively), but is significantly greater than<br />
Hadite, another heat-expanded aggregate (23 per cent) and bottom<br />
ash (20 per cent) recycled from a coal-power facility.<br />
G.R.E.E.N.’s experimental results are designed to aid those wishing<br />
to implement green roof systems by developing a “prescription” <strong>for</strong><br />
each green roof application. It is our goal that a series of questions<br />
about each green roof installation can be addressed and a prescription<br />
containing the proper green roof plant list and growing medium<br />
be developed <strong>for</strong> use in each commercial green roof installation<br />
plan. We invite you to visit our website <strong>for</strong> more results at<br />
www.green-siue.com/researchresults.html. <br />
Dr. Bill Retzlaff chair of the Department of Biological Sciences,<br />
Southern Illinois University Edwardsville and research coordinator of<br />
the St. Louis metropolitan area research collaboration (G.R.E.E.N.).<br />
Dr. Susan Morgan is chair of the Civil Engineering Department, Southern<br />
Illinois University Edwardsville and research member of G.R.E.E.N.<br />
Kelly Luckett is president of <strong>Green</strong> Roof Blocks, Florissant, Missouri<br />
and industry-collaborator member of G.R.E.E.N.<br />
Mr. Vic Jost is co-owner of Jost <strong>Green</strong>houses, Des Peres, Missouri<br />
and industry-collaborator member of G.R.E.E.N.
CREATINGHABITAT<br />
BYDESIGN<br />
RESEARCHERSHAVEDEVELOPEDANEWPROCESSMODEL—USINGTHEDICKCISSELSPIZA<br />
AMERICANAATHREATENEDGRASSLANDBIRDASANEXAMPLE—TOHELPGREENROOFERS<br />
MAKETHERIGHTDECISIONSWHENTRYINGTORESTOREHABITATFORASPECIFICSPECIES<br />
By Dr. Reid Coffman and Allison Thurmond<br />
Great Plains grassland bird populations have plummeted in<br />
response to fragmented grasslands and a growing presence of<br />
agricultural chemicals in surviving habitat. In addition to the restoration<br />
and conservation needed to protect grasslands, Michael Rozenweig’s<br />
idea of “reconciliation ecology” seeks to pick up where the two leave<br />
off, at the edges of development.<br />
Preliminary studies indicate strong potential <strong>for</strong> reconciling habitat on<br />
urban rooftops. To further advance the idea, a green roof was proposed<br />
as nesting habitat <strong>for</strong> the Dickcissel (Spiza Americana), a migratory<br />
ground-nester (pictured above). The species was chosen <strong>for</strong> its adaptability,<br />
height threshold, and threatened status. From this we designed a<br />
new habitat based on the Dickcissel’s environmental needs to demonstrate<br />
the ease of applying a habitat template approach to green roof<br />
ecological design.<br />
Our green roof habitat design is a template which is intended to mimic<br />
the environment based on the species-specific in<strong>for</strong>mation such as soil<br />
needs, prey population and nesting behaviors — and provides a model <strong>for</strong><br />
other designers to consider when designing <strong>for</strong> ecological restoration.<br />
The design process is organized into seven explicit steps, which aid in<br />
matching appropriate wildlife species to a functional green roof system.<br />
The contextual in<strong>for</strong>mation is directed to suburbanizing communities<br />
practicing bird conservation in the southern Great Plains, while the<br />
template concept holds a universal application in ecoroof habitat design.<br />
Several constants are locally available materials, and appropriate<br />
indigenous species and creation of diverse habitat.<br />
One key variable to habitat establishment is matching plant<br />
species to substrate mixes. For central Oklahoma, the Permian<br />
shale outcroppings found to our west are an ideal example of<br />
the drier, windier, hotter, and rockier conditions that a rooftop<br />
condition imposes. The Dickcissel’s need <strong>for</strong> tall vegetation led to<br />
a projected substrate depth of 15" to 24": deep enough to support<br />
a selection of shallow-rooted native plants with a structure that<br />
mimics the archetypical deep-rooted prairie species. Materials<br />
like crushed brick, lightweight expanded clay, and cottonseed<br />
hulls (lightweight, water-retaining agricultural byproduct) mixed<br />
with clean topsoil, sand and gravel are used in different proportions<br />
to maintain a diverse environment and lower the overall<br />
weight of the roof.<br />
Plants are then selected based on several key factors, found in the<br />
Plant Rationale Key (see next page). The rational underscore the most<br />
important needs of the nesting pair, but may vary by keystone species.<br />
<br />
LIVING ARCHITECTURE MONITOR<br />
WINTER
“The design process is<br />
organized into seven<br />
explicit steps, which aid<br />
in matching appropriate<br />
wildlife species to a functional<br />
green roof system.”<br />
In this case, Elbowbush (Forestiera pubescens), a shallow rooted Plains<br />
bush provided structure while Sand Dropseed (Sporobolus cryptandrus)<br />
and Idaho Fescue (Festuca idahoensis) served as grassy height and <strong>for</strong>age.<br />
Shale adapted Blue Grama (Bouteloua gracilis) holds soil and native<br />
<strong>for</strong>bs like Evening Primrose (Oenothera speciosa) and Beebalm<br />
(Monarda fistulosa) sustain insect populations. Finally, edging the building<br />
with trees supplements woody height and eases transition to the roof.<br />
The project in<strong>for</strong>mation is currently being used to educate local officials<br />
and designers on the use of a template approach to green roof<br />
habitat. It is our hope this step-by-step model will assist you in creating<br />
restorative habitats on green roofs and walls. <br />
THESEVENDESIGNSTEPS<br />
FROMIDENTIFICATIONTOFINALHABITAT<br />
STEP<br />
identify a threatened bird species in need of nesting habitat<br />
STEP<br />
locate under-utilized, low slope roof<br />
STEP<br />
confirm that your roof is adjacent to open land<br />
STEP<br />
be creative with locally available materials <strong>for</strong> the growing<br />
substrate<br />
STEP<br />
calculate the substrate’s weight and the structure you’ll need to<br />
support it<br />
STEP<br />
design your base substrate<br />
STEP<br />
design the nesting habitat, focusing on indigenous plants and<br />
biodiversity<br />
RECOMMENDEDREADINGS<br />
Brenneisen, S. (2003). Biodiversity of European <strong>Green</strong>roofs. In conference<br />
proceedings of <strong>Green</strong>ing Rooftops <strong>for</strong> Sustainable Communities<br />
Chicago, Illinois. <strong>Green</strong> <strong>Roofs</strong> <strong>for</strong> <strong>Healthy</strong> <strong>Cities</strong>.<br />
Coffman, R. (2007). Comparing Wildlife Habitat and Biodiversity<br />
Across <strong>Green</strong> Roof Type. In the conference proceedings of <strong>Green</strong>ing<br />
Rooftops <strong>for</strong> Sustainable Conference, Minneapolis, Minnesota,<br />
<strong>Green</strong> <strong>Roofs</strong> <strong>for</strong> <strong>Healthy</strong> <strong>Cities</strong>.<br />
Lundholm, J. (2006). <strong>Green</strong> <strong>Roofs</strong> and Facades: A Habitat Template<br />
Approach. Urban Habitats Dec. Vol 4, Issue 1, pages 87 — 101.<br />
Rozenweig, M. L. (2003) Win-Win Ecology: How the Earth’s Species Can<br />
Survive in the Midst of Human Enterprise. Ox<strong>for</strong>d University Press.<br />
Dr. Reid Coffman, Ph.D. is an assistant professor of landscape architecture<br />
at the University of Oklahoma. He is a founding member of the International<br />
Research Committee <strong>for</strong> <strong>Green</strong> <strong>Roofs</strong> <strong>for</strong> <strong>Healthy</strong> <strong>Cities</strong> and<br />
a past fellow with the National Wildlife Federation. He holds degrees in<br />
urban ecology, environmental horticulture and landscape architecture.<br />
Allison Thurmond is a fifth year architecture student at the<br />
University of Oklahoma based in Norman, Oklahoma, with a focus<br />
on Environmental Studies and Anthropology. She is also a LEED®<br />
accredited professional and a National Merit Scholar.<br />
PLANTRATIONALEKEY<br />
USETHISGUIDETODETERMINEPLANSUITABILITY<br />
F/FORAGE<br />
produce seeds eaten by the Dickcissel<br />
N/NESTING<br />
locate under-utilized, low slope roof<br />
C/COVER<br />
provides height and protection <strong>for</strong> the Dickcissel and its insects<br />
I/INSECTATTRACTOR<br />
sustains invertabrate communities needed as a <strong>for</strong> source <strong>for</strong><br />
nesting Dickcissel pairs<br />
W/EVERGREEN<br />
maintains evapotranspiration and insulating plant material year<br />
round, improving the per<strong>for</strong>mance of the roof<br />
E/EROSIONCONTROL<br />
helps hold substrate in place, a concern with the additional wind<br />
and runoff erosion stresses on an elevated habitat<br />
S/SOILFIXER<br />
maintains or replaces nitrogen and organic matter in the soil, critical<br />
<strong>for</strong> long-term success <strong>for</strong> the roof
POLICY<br />
SEATTLE’SGREENFACTOR<br />
ANEWURBANLANDSCAPINGPOLICYISPUTTINGMOREGREENROOFSANDWALLS<br />
PROJECTSONTHEBOOKSINTHISCOASTALCITY<br />
By Lillian Mason & GRHC staff<br />
Seattle’s vision to increase green space in its urban areas through the<br />
implementation of a new landscaping requirement is starting to pay<br />
off with steady growth in green roofs and green wall projects.<br />
Since January of last year, developers and designers of new construction<br />
projects planned <strong>for</strong> either Seattle’s neighborhood business districts<br />
or commercially zoned areas must demonstrate how they intend<br />
to meet the city’s new landscaping requirement — or no building permit<br />
will be issued by its Department of Planning and Development. It’s<br />
called “Seattle <strong>Green</strong> Factor” and builds on the “Biotope Area Factor”<br />
developed by Carlo Becker and already being applied in Germany<br />
and parts of Sweden.<br />
The Seattle idea stems back to a talk by Melissa Keeley, who received<br />
her doctorate from the Institute of Landscape <strong>Architecture</strong> and Environmental<br />
Planning at the Technical University of Berlin. Her presentation<br />
on “The <strong>Green</strong> Area Ratio,” at a GRHC meeting in Denver, was heard by<br />
an interested engineer who passed the info over to the city of Seattle<br />
LANDSCAPINGMENU<br />
The Seattle <strong>Green</strong> Factor is a menu of landscaping strategies, each with<br />
an assigned point value. Landscaping strategies incorporating asphalt,<br />
concrete and conventional roofs, <strong>for</strong> instance, have no value. Permeable<br />
paving, green roofs and green walls, on the other hand, are among the<br />
highest-value landscaping options (see “The <strong>Green</strong> Factors,” next page).<br />
Bonuses are given <strong>for</strong> rainwater harvesting and or low-water-use plantings.<br />
The ultimate idea is to encourage the planting of layers of vegetation and<br />
larger trees in areas visible to the public and in public rights-of-way.<br />
Projects must meet minimum landscaping scores — the so-called “green<br />
factor” — and submit those scores along with their other planning documents,<br />
including a plan, worksheet and a chart explaining how the score<br />
was achieved. The minimum score <strong>for</strong> any commercially zoned land is<br />
0.3, which means a project must plan <strong>for</strong> the equivalent of 30 per cent<br />
of the parcel area committed to urban landscaping. In practice, however,<br />
it takes up much less than that of the footprint, through the layering<br />
and bonus options. For buildings that entirely cover their lot you can<br />
meet the minimum requirement by simply covering half of your roof.<br />
The factors were originally developed by Mr. Becker to reflect the watershed<br />
value of these various landscape treatments. Seattle started<br />
with the Biotope Area Factors and then nudged up or down to better<br />
reflect local conditions.<br />
Seattle’s Department of Planning and Development created a worksheet<br />
that helps applicants calculate their projects score, enabling<br />
them to use different combinations of green features to reach the<br />
minimum requirement.<br />
For example, one small mixed-use development in a neighborhood business<br />
district was able to meet the Seattle <strong>Green</strong> Factor score by adding<br />
a small green roof, cascading vegetation across a portion of the façade,<br />
and a vegetated wall along the back alley.<br />
Since implementation of the Seattle <strong>Green</strong> Factor on Jan. 20, 2006,<br />
over 50 projects have used the online worksheet to calculate their<br />
options, with many choosing green roofs and walls to raise their<br />
scores. In fact, says Steve Moddemeyer, senior strategic advisor at<br />
the Seattle Department of Planning and Development, judging from<br />
the plans they are seeing, green walls are proving to be very popular<br />
urban landscaping choices.<br />
“The vegetative walls really don’t take up much of the overall building<br />
footprint, but have the highest credit value,” he explains. “What we’re<br />
“What we’re seeing is that<br />
green walls are becoming a<br />
very strong element of the<br />
overall design, sometimes<br />
even the focal point.”<br />
Steve Moddemeyer, Seattle Department of Planning & Development<br />
(pictured left)
seeing is that green walls are becoming a very strong element of the<br />
overall design, sometimes even the focal point. It appears more designers<br />
and developers are asking themselves, ‘How do we integrate a<br />
green wall into our project in a way that is both functional and aesthetically<br />
pleasing?’ It’s what we hoped would happen.”<br />
Like any new public policy, however, Seattle’s <strong>Green</strong> Factor is not<br />
without the odd challenge. Public utilities must review and approve<br />
any landscaping plans that cover a public-right of way such as a<br />
sidewalk. So developers and designers original plans may not always<br />
get approved if such things as trees and shrubs are conflicting<br />
with a planned or existing public utility such as an electrical<br />
box. Also, public utilities may or may not allow alternative methods<br />
<strong>for</strong> dealing with stormwater runoff from development so that could<br />
potentially constrain opportunities. At the same time, says Moddemeyer,<br />
it will also highlight the need <strong>for</strong> public utilities to better<br />
understand innovative new urban landscaping opportunities and<br />
their public benefits.<br />
The Seattle <strong>Green</strong> Factor has been working so well that the city is<br />
now proposing the expansion of its application to multi-family zones,<br />
where green spaces are larger and would require higher standards.<br />
“In these areas, where there can be side-yard setbacks and openspace<br />
requirements we are considering a required score of 0.75,” explains<br />
Moddemeyer. “We are just beginning our public process, so it<br />
will be interesting to see how that level fares in the debate.”<br />
Incidentally, Keely who is a fellow at The Earth Institute at Columbia<br />
University in New York, has received two federal grants in order to<br />
research how to implement “The <strong>Green</strong> Area Ratio” in Philadelphia<br />
and Washington D.C <br />
<strong>Green</strong> Roof <strong>for</strong> <strong>Healthy</strong> <strong>Cities</strong>’ staff with files from Lillian Mason, a freelance<br />
writer based in Toronto, Canada with an interest in green building.<br />
RESOURCES<br />
To see the Seattle <strong>Green</strong> Factor online worksheet, visit<br />
www.seattle.gov/dpd/permits/greenfactor.<br />
Graphic by Liz Martini; illustrations by Jeff Benesi. Image courtesy of Seattle’s Department of Planning and Development.
POLICY<br />
“BUSHTOPS”DOWNUNDER<br />
ADELAIDE'SINNOVATIVEGREENWALLANDROOFINCENTIVEPOLICYSETTOBEA<br />
MODELFOROTHERAUSTRALIANCITIES<br />
By Graeme Hopkins & Christine Goodwin<br />
The South Australian Government is leading the development of an<br />
innovative green roof and living wall incentive policy structure to<br />
bring the Australian “bush” into the city of Adelaide — and the program<br />
could be a model <strong>for</strong> other cities.<br />
A series of living walls and green rooftops or “bushtops” that mimic<br />
the endemic ecosystems of the original landscape of the city of<br />
Adelaide are planned. Individual projects will be linked together to<br />
<strong>for</strong>m stepping-stone wildlife corridors across the central business<br />
district to restore the original migration patterns of birds, insects<br />
and certain animals.<br />
<strong>Green</strong> walls will connect the bushtops to the ground and allow the<br />
passage of animals and insects between the vertical and horizontal<br />
planes. The projects will be carefully integrated with current research<br />
at the School of Urban Ecology at the University of South<br />
Australia and it’s expected that Planning SA’s program will be a<br />
major plat<strong>for</strong>m <strong>for</strong> the reintroduction of species back into Adelaide’s<br />
urban environment.<br />
Planning SA’s program, Bushtops <strong>for</strong> <strong>Green</strong> <strong>Roofs</strong> and Walls, will<br />
include a unique green roof and living wall incentive program <strong>for</strong><br />
government buildings and projects. Often with many government<br />
agencies, monies <strong>for</strong> incentive programs are limited and very competitive,<br />
so a pioneering idea may have very little leverage to attract<br />
funding. However, under this new incentive program, government<br />
projects can now access design and development services via<br />
Planning SA’s principal urban designer’s expertise in green roof and<br />
living wall design. This is a free service <strong>for</strong> government projects to<br />
encourage the inclusion of green roofs and walls into their sustainable<br />
projects. This is an effective way to incorporate this green<br />
technology into new buildings or revitalisation projects in Adelaide.<br />
The City of Adelaide is also actively promoting green roofs on<br />
residential buildings through its Rooftop Gardens Fact Sheet — a<br />
document that provides homeowners with examples of rooftop<br />
garden layouts and suggested planting lists to achieve a sustainable<br />
green roof. The Fact Sheet also explains benefits to city residents<br />
of living architecture: improved lifestyle, reduced costs, improved<br />
property values, residents com<strong>for</strong>t, natural attraction, water<br />
conservation, improved air quality and reduced air temperatures.<br />
Fifth Creek Studio’s first bushtop project on the fourth floor of a<br />
community housing development at Hocking Place (see above) in<br />
Adelaide was supported by government and recently won the Australian<br />
Institute of Landscape Architects SA Award <strong>for</strong> Residential<br />
<br />
LIVING ARCHITECTURE MONITOR<br />
WINTER
THEGROWINGMEDIA&PLANTISSUE<br />
Fifth Creek Studio<br />
PREVIOUSPAGEColorful "Kangaroo Paw" plants attract birds and insects to a residential high-rise rooftop in Australia. THISPAGELEFTA bat box creates<br />
an attractive habitat <strong>for</strong> microbats on the green roof at Hocking Place in Adelaide — and the residential buildings tenants are grateful <strong>for</strong> fewer mosquitoes and<br />
Australia’s pesky flying ants. THISPAGERIGHTClimbing native plants provide shade <strong>for</strong> residents of Adelaide’s Hocking Place’s award-winning “bushtop”<br />
designed by Fifth Creek Studio.<br />
“Several city-wide projects are<br />
in the conceptual development stage,<br />
including a new state government<br />
hospital featuring green roofs.”<br />
Design, and a Special Citation <strong>for</strong> Future Directions <strong>for</strong> <strong>Cities</strong>. The<br />
bushtop is an accessible intensive green roof, combining animal and<br />
insect habitat with passive recreational access by the residents of the<br />
building’s 15 apartments.<br />
Particular species of small birds that were once common in the Adelaide<br />
Plains were targeted by planting selected native grasses and<br />
sedges, and flowering plants to attract butterflies and other insects. A<br />
bat box attracts microbats, useful in the control of mosquitoes and flying<br />
ants. The bat box is being monitored during summer months as part<br />
of Adelaide City Council’s Bat Track program. If this box is successfully<br />
colonized other boxes may be added.<br />
The Hocking Place project is now a demonstration project <strong>for</strong> promotion<br />
of the bushtop concept within state and local government authorities. By<br />
combining the success of this first project with Planning SA’s attractive incentive<br />
program, the concept of stepping-stone corridors can be realised.<br />
Several city-wide projects are in the conceptual development stage,<br />
including a new state government hospital featuring green roofs at<br />
various levels, and proposed redevelopment infill residential projects<br />
with green roofs and walls as part of the open space recreation<br />
requirements. These projects are <strong>for</strong>ming elements within the stepping-stone<br />
corridors throughout the city. <br />
Graeme Hopkins and Christine Goodwin are landscape architects and<br />
directors of Fifth Creek Studio located in Adelaide, Australia. Together,<br />
they have researched bushtops in cities <strong>for</strong> more than five years.<br />
Additionally, Graeme is the government’s Planning SA’s Principal Urban<br />
Designer with a role to focus on environmental sustainability and<br />
intensified population density in the metropolitan context including the<br />
bushtop policy project in Adelaide.<br />
RESOURCES<br />
Fifth Creek helped develop the Rooftop Gardens Fact Sheet <strong>for</strong> the<br />
City of Adelaide (to be on the Adelaide City Council website soon:<br />
www.adelaidecitycouncil.com<br />
To learn more, please also see <strong>Green</strong> <strong>Roofs</strong> <strong>for</strong> <strong>Healthy</strong> Australian<br />
<strong>Cities</strong>, a new industry association developing green roofs and walls in<br />
Australia at www.greenroofs.org/au<br />
LIVING ARCHITECTURE MONITOR WINTER
GRHCUPDATE<br />
AVERTICALOASIS—MFOPARKINZURICHSWITZERLAND<br />
GREENWALL<br />
TECHNOLOGYCLIMBING<br />
<strong>Green</strong> <strong>Roofs</strong> <strong>Healthy</strong> <strong>Cities</strong> is branching<br />
out beyond green roofs and into green<br />
walls that involve the use of a variety of<br />
exciting new technologies that integrate<br />
plants with the facades of buildings <strong>for</strong><br />
multiple benefits and integration potential.<br />
In early fall of 2006 Steven Peck, president of<br />
GRHC brought together various green<br />
wall system manufacturers and together they<br />
struck a <strong>Green</strong> Wall Sub-Committee. Their<br />
first order of business was to combine<br />
resources and expertise to develop a new<br />
training course <strong>for</strong> green walls with expert<br />
assistance from Randy Sharp, principal of<br />
Sharp and Diamond, and a long time advocate<br />
and designer of green walls. This ef<strong>for</strong>t led to<br />
the development of <strong>Green</strong> Walls 101: Introduction<br />
to Systems and Design, launched at the<br />
<strong>Green</strong>ing Rooftops <strong>for</strong> Sustainable Communities<br />
conference in Minneapolis last May.<br />
The new <strong>Green</strong> Wall course, the first in North<br />
America, provides an overview of the many<br />
tools and techniques needed to satisfy greenwall<br />
project objectives, the major functions and<br />
characteristics of components and systems<br />
available in the marketplace, as well as benefits<br />
and policy programs driving this industry <strong>for</strong>ward.<br />
Since its launch the course has been delivered<br />
in San Francisco, Boston, Chicago, New<br />
York, Washington, Vancouver and Toronto to<br />
over 300 professionals.<br />
The upcoming 6th Annual <strong>Green</strong>ing<br />
Rooftops <strong>for</strong> Sustainable Communities Conference<br />
in Baltimore will mark another first<br />
<strong>for</strong> the <strong>Green</strong> Walls Sub-Committee, with<br />
the introduction of a green walls category in<br />
the <strong>Green</strong> Roof Awards of Excellence program.<br />
The new award will recognize green<br />
wall projects that exhibit extraordinary leadership<br />
in integrated design and implementation<br />
of green walls. It will also help increase<br />
general awareness of green wall infrastructure<br />
and its associated public and private<br />
benefits, while recognizing the valuable contributions<br />
of green wall design professionals.<br />
The <strong>Green</strong> Wall Sub-Committee, chaired<br />
by Reuben Freed, greenscreen®, is also<br />
beginning to develop a green wall research<br />
program. It will establish a research fund and<br />
is exploring strategies to stimulate research<br />
that will fall in line with the USGBC and<br />
CanGBC LEED® rating systems.<br />
The six LEED® categories (taken from the<br />
LEED® 2.1 <strong>for</strong> Non-Commercial buildings<br />
checklist) which will guide the scope of the<br />
project include are: Sustainable Sites; Water<br />
Efficiency; Energy & Atmosphere; Materials<br />
and Resources; Indoor Environmental Quality;<br />
and, Innovation & Design Process. It is the<br />
sub-committee’s hope that this in<strong>for</strong>mation<br />
will facilitate the explicit inclusion of green<br />
walls in the LEED® rating system and increase<br />
the rates of green wall construction throughout<br />
North America.<br />
The sub-committee is also is working to<br />
establish a green wall image, project in<strong>for</strong>mation<br />
and incentive database, which will<br />
Photo courtesy of Jakob<br />
<br />
LIVING ARCHITECTURE MONITOR<br />
WINTER
THEGROWINGMEDIA&PLANTISSUE<br />
profile different green wall systems and<br />
applications on various building types across<br />
the continent. The database will act as a<br />
tool to support LEED® ef<strong>for</strong>ts and project<br />
specific research <strong>for</strong> building owners and<br />
designers.<br />
Reuben Freed, attributes the early success of<br />
green walls thus far to the technology’s “intuitive<br />
and visceral appeal; green walls bring a<br />
natural exuberance to designed structures,<br />
and deliver a maximum of beauty from a minimum<br />
requirement of space, providing shade,<br />
privacy, com<strong>for</strong>t and vital, visual relief from<br />
the hardscape surrounding us.”<br />
LEARNMOREABOUT<br />
GREENROOFSANDWALLS<br />
GRHC’SPROFESSIONALCOURSECALENDARISNOW<br />
ONLINE—ANDTHEREAREMORECOURSESTHANEVER<br />
INNORTHAMERICANCITIES<br />
The 2008 Course Calendar is now available online and is sorted by city and date. Over 100<br />
green roof and wall courses will be delivered in over 30 North American cities throughout<br />
the year. Visit www.greenroofs.org to view the schedule or to register <strong>for</strong> any one of these<br />
popular daylong courses.<br />
The sub-committee’s four-part approach<br />
promises to lay solid foundations <strong>for</strong> rapid<br />
growth and development of green walls,<br />
an exciting new approach to implementing<br />
living architecture and restorative and<br />
healing buildings. www.greenroofs.org <br />
GREENWALLDESIGNERS<br />
Visit the web site <strong>for</strong> Awards of Excellence contest details or contact the awards administrator<br />
at awards@greenroofs.org <strong>for</strong> more in<strong>for</strong>mation. <strong>Green</strong> Wall courses in 2008<br />
will be posted on www.greenroofs.org regularly<br />
By Flavia Bertram
GRHCUPDATE<br />
OMAHAWELCOMESOPPORTUNITY<br />
TOBUILDMOREGREENROOFS<br />
STORMWATERMANAGEMENTAMONGTHETOPICSATRECENTNEBRASKAN-BASEDLOCAL<br />
MARKETDEVELOPMENTSYMPOSIUM<br />
Over 60 participants attended the Oct. 25,<br />
2007 Omaha-GRHC <strong>Green</strong> <strong>Roofs</strong> Symposium,<br />
hosted by Douglas County and the<br />
City of Omaha, Nebraska and co-sponsored<br />
by Omaha’s Metropolitan Community College.<br />
The Nebraska Department of Environmental<br />
Quality’s Stormwater Management<br />
Plan Program provided partial funding <strong>for</strong><br />
the symposium.<br />
Omaha Mayor Mike Fahey and Douglas<br />
County Commissioner Pam Tusa kicked off<br />
the symposium with welcoming remarks.<br />
“In 2006, I signed the U.S. Mayor’s Climate<br />
Protection Agreement joining the now 600<br />
United States mayors committed to helping<br />
stop the advancement of global warming,”<br />
said Omaha Mayor Mike Fahey in a statement<br />
about why green roofs are important. “By encouraging<br />
more green roofs and walls in and<br />
around Omaha, we have the opportunity to<br />
reduce greenhouse gas emissions and create<br />
a healthier city <strong>for</strong> generations to come.”<br />
<strong>Green</strong> roof case studies were presented by<br />
Richard Sutton of the University of Nebraska-<br />
Lincoln on a new green roof project in Lincoln,<br />
Nebraska at the Pioneer’s Park Nature<br />
Center and then by Kevin Schluckebier of the<br />
architectural firm Berringer, Ciaccio, Dennel<br />
and Mabrey on the proposed Saddlebrook<br />
joint-use facility in Omaha.<br />
Keynote speaker Jeffrey L. Bruce of the Jeffrey<br />
Bruce Company of Kansas City gave an<br />
in-depth presentation on key aspects of green<br />
roofs along with examples of some of his firm’s<br />
outstanding projects.<br />
Afternoon focus groups on stormwater management<br />
and retrofitting buildings rounded<br />
out the symposium. Input from these focus<br />
groups will in<strong>for</strong>m the development of an action<br />
plan to promote the use of green roofs in<br />
the Omaha metropolitan area.<br />
The University of Nebraska-Lincoln’s Sutton<br />
says he was impressed with the turn-out <strong>for</strong><br />
“ By encouraging more green<br />
roofs and walls in and<br />
around Omaha, we have the<br />
opportunity to reduce<br />
greenhouse gas emissions<br />
and create a healthier city<br />
<strong>for</strong> generations to come.”<br />
Mike Fahey, Mayor of Omaha, Nebraska<br />
the meeting. “Just be<strong>for</strong>e I gave my talk, I<br />
surveyed the audience and was pleased to<br />
find it pretty evenly split into four groups: engineers,<br />
architects, landscape architects and<br />
green industry professionals,” he observed.<br />
“<strong>Green</strong> roofs have truly become a vehicle <strong>for</strong><br />
interdisciplinary collaboration.” He hopes a<br />
support group to continue the dialogue<br />
between various groups will move <strong>for</strong>ward.<br />
By Kent E. Holm<br />
Kent E. Holm is the Environmental Services<br />
Director <strong>for</strong> Douglas County, Nebraska.<br />
RESEARCH<br />
COMMITTEEREPORT<br />
The <strong>Green</strong> Roof Research Committee has had<br />
an active summer and fall. Brad Rowe has<br />
passed the duties of the Chair to Dr. Brad Bass<br />
from Environment Canada. The committee approved<br />
the creation of a Data Repository <strong>for</strong><br />
green roof data that has been collected at different<br />
sites across North America. The committee<br />
is now accepting nominations <strong>for</strong> two<br />
awards to be presented at the annual conference<br />
in Baltimore. One <strong>for</strong> best research<br />
paper, the second, recognition of a long-term<br />
achievement in green roof research. Details<br />
and submission <strong>for</strong>ms are available at<br />
www.greenroofs.org or contact the awards<br />
administrator at awards@greenroofs.org.<br />
Update by Dr. Brad Bass, co-chair, GRHC<br />
Research Committee<br />
LOCAL<br />
CHAMPIONS<br />
WANTED!<br />
Want to see what other local champions<br />
are doing to promote the green roof and<br />
green wall industry across North America?<br />
Check out www.greenroofs.org and<br />
click on the Symposia button to connect<br />
to local champion materials by city including<br />
the action plans developed during<br />
the symposiums. They could be a<br />
blueprint <strong>for</strong> your city!<br />
<br />
LIVING ARCHITECTURE MONITOR<br />
WINTER
SCIENTIFIC<br />
INTEREST<br />
GREENROOFSDEBUTIN<br />
INFLUENTIALJOURNALS<br />
Two prestigious, internationally profiled peer<br />
reviewed magazines are publishing green roof<br />
research developed by GRHC members.<br />
BioScience which was published last November<br />
features a multidisciplinary synthesis on green<br />
roof research co-authored by GRHC members<br />
including Jeremy Lundholm Ph.D, assistant<br />
professor of Biology and Environmental Studies<br />
at Saint Mary’s University in Halifax; Dr.<br />
Brad Bass, with the Institute <strong>for</strong> Environmental<br />
Studies, Environment Canada at the University<br />
of Toronto; and Bradley Rowe, professor of<br />
Horticulture at Michigan State University.<br />
Urban Ecosystems journal will be publishing a<br />
special edition on green roof research. The<br />
idea originated from a GRHC research committee<br />
meeting and will have a special emphasis<br />
on urban ecology.<br />
Lundholm, who will be guest editing the Urban<br />
Ecosystems issue, is pleased green roof<br />
research is branching into different areas. He<br />
explains that not many biologists are working<br />
with green roof systems — mostly it has been<br />
engineers, urban planners and horticulturalists.<br />
Calculating habitat value and promoting biodiversity<br />
on green roofs is expanding. Other<br />
areas of research that may be featured are<br />
psychology, social sciences and health.<br />
By Lillian Mason<br />
WANTAGREENROOF<br />
SYMPOSIUMINYOURCITY?<br />
Are you interested in co-hosting a<br />
GRHC sponsored symposium in your city?<br />
If so, please contact Jennifer Sprout at<br />
416.971.4494 ext. 229 or<br />
jsprout@greenroofs.org
GRHCUPDATE<br />
SYMPOSIUMIGNITESGREENROOF<br />
ANDWALLMOMENTUMINATLANTA<br />
FROMARCHITECTSTOPUBLICPOLICYMAKERS—THEFINESTPROFESSIONALSGATHERED<br />
TOBRAINSTORMANACTIONPLANFORMOREGREENROOFSANDWALLSINGEORGIA’S<br />
CAPITALCITY<br />
By Lillian Mason & GRHC staff<br />
GRHC Symposiums' continue in cities<br />
across North America, developing the<br />
sector and kick-starting projects that engage<br />
professionals throughout the green<br />
roof and wall industry. One of the organization’s<br />
latest symposium stops was Atlanta —<br />
sparking excitement, energy and cooperation<br />
among Georgia-based professionals<br />
and policymakers interested in green roofs.<br />
The event, held in September 2007, was attended<br />
by a wide array of architects, students,<br />
planners, non-profits, engineers and<br />
landscape architects. Kelly Caffarelli of the<br />
Home Depot Foundation, a lead sponsor of<br />
the event, welcomed participants with her<br />
opening remarks, followed by Clair Muller, an<br />
Atlanta City council member <strong>for</strong> District 8.<br />
Participants then heard from several Georgia<br />
designers, advocates and researchers who<br />
presented case studies of several existing<br />
green roofs projects in the Atlanta-area.<br />
Dan Gerding, AIA, of Gerding Collaborative<br />
shared his involvement with several regional<br />
projects including: Georgia’s Sweetwater<br />
Creek State Park Visitor Center, a LEED®platinum<br />
certified building opened in July<br />
2006 (see images above and right); and the<br />
recently completed NeoTerra Townhomes in<br />
Atlanta featuring a half-an-acre extensive<br />
residential green roof with underground<br />
rainwater cisterns <strong>for</strong> site irrigation and<br />
stormwater management. Other presenters<br />
included Meg Needle from architect firm<br />
Lord, Aeck, Sargent sharing details of one of<br />
their exciting projects, the Gwinett Environmental<br />
and Heritage Center in Gwinnett<br />
County, GA, a site with an extensive green<br />
roof, rain chains and native plants.<br />
As with every GRHC-sponsored Symposium,<br />
part of the agenda was devoted to<br />
identifying barriers to green roof implementation<br />
— and Atlanta was no exception.<br />
Here, Art Gibert, a planner from the GA Department<br />
of Community Affairs and other<br />
participants expressed their concerns about<br />
what they felt were the major issues including<br />
costs associated with green roofs, lack<br />
of incentives, potential leaks and liability issues,<br />
as well as maintenance and a general<br />
apathy towards energy conservation.<br />
But problem identification is only the beginning;<br />
the next step is a brainstorming<br />
“The symposium<br />
and training<br />
provided<br />
inspiration<br />
and hope <strong>for</strong><br />
Atlanta — not to<br />
mention vital<br />
in<strong>for</strong>mation —<br />
<strong>for</strong> the future<br />
of society and<br />
our world.”<br />
Art Gibert, planner <strong>for</strong> the State of Georgia &<br />
Atlanta Symposium participant<br />
<br />
LIVING ARCHITECTURE MONITOR<br />
WINTER
THEGROWINGMEDIA&PLANTISSUE<br />
FROMTHE<br />
ACCREDITATION<br />
SUB-COMMITTEE<br />
session leading to the development of an<br />
Action Plan, which in the case of Atlanta’s<br />
Symposium included the establishment of<br />
an Atlanta <strong>Green</strong> Roof Steering Committee<br />
and “smart growth” strategies.<br />
Other action items included the<br />
exploration of potential partnerships and<br />
a proposal <strong>for</strong> providing incentives <strong>for</strong><br />
green roofs in Chamblee, a smaller city<br />
outside Atlanta, also emerged from the<br />
event and will be discussed by the new<br />
Atlanta <strong>Green</strong> Roof Steering Committee<br />
after newly elected officials take office in<br />
early 2008.<br />
Also, the city of Atlanta is considering an<br />
ordinance to require LEED® certification<br />
<strong>for</strong> all public projects and any private development<br />
over 50,000 square feet. This is<br />
a first in Georgia, there<strong>for</strong>e an important<br />
prospect, being that green roofs can be<br />
used to achieve many LEED® points.<br />
The long-term impact of the symposium is<br />
likely to include a more directed ef<strong>for</strong>t toward<br />
getting green roofs and green walls<br />
recognized as solutions that can mitigate<br />
and reduce many of the Atlanta’s pressing<br />
energy and water conservation challenges.<br />
“<strong>Green</strong> roofs offer a magnificent opportunity<br />
to improve humankind’s relationship to<br />
the environment and the problems of shelter<br />
and lifesupport,” noted Gibert after the<br />
event. “The symposium and trainings offered<br />
by <strong>Green</strong> <strong>Roofs</strong> <strong>for</strong> <strong>Healthy</strong> <strong>Cities</strong><br />
provided inspiration and hope <strong>for</strong> Atlanta —<br />
not to mention vital in<strong>for</strong>mation — <strong>for</strong> the<br />
future of society and our world.” <br />
FIRSTGREENROOFPROFESSIONALACCREDITATION<br />
EXAMPLANNEDFORCONFERENCEIN<br />
ATLANTAGEORGIA<br />
Behind the scenes at GRHC, the organization<br />
continues to develop an industry-wide<br />
Accreditation Program. To this end, we are<br />
working with a dedicated team of subjectmatter<br />
experts to develop the final course<br />
in our program — Plants and Growing<br />
Medium 401. Simultaneously, we have been<br />
working on the development of the Accreditation<br />
Model that would be most appropriate<br />
to establish the Accredited <strong>Green</strong> Roof<br />
Professional designation.<br />
To accomplish this goal, we <strong>for</strong>med an Accreditation<br />
Sub-Committee, chaired by Professor<br />
Virginia Russell of the University of<br />
Cincinnati in Ohio. The main focus <strong>for</strong> this<br />
sub-committee was the review of a variety of<br />
other accreditation/certification models currently<br />
used by organizations such as the U.S.<br />
<strong>Green</strong> Building Council, RCI, and ANLA etc.<br />
To date, the sub-committee has concluded<br />
that the most appropriate model <strong>for</strong> GRHC<br />
would be one similar to the LEED® accreditation<br />
model. This would mean an accreditation<br />
exam would be available to a broad range of<br />
potential candidates without any prerequisites.<br />
The test itself will be based on the<br />
multi-disciplinary material in our Occupational<br />
Standards, completed over a year ago.<br />
This knowledge is covered in GRHC courses,<br />
which while highly recommended, will not be<br />
a requirement prior to taking the test.<br />
Although we have made significant progress,<br />
there is still much work to be done. First we<br />
must complete the development of the 401<br />
Course <strong>for</strong> delivery at GRHC’s Sixth Annual<br />
International <strong>Green</strong>ing Rooftops <strong>for</strong> Sustainable<br />
<strong>Cities</strong> Conference in Baltimore this<br />
spring (April 30–May 2, 2008). Second, we<br />
need to develop the written test and make<br />
critical decisions regarding the maintenance<br />
of the Accreditation designation through such<br />
mechanisms as continuing education credits.<br />
To assist us with the test development, we will<br />
be working with Prometric, a company with<br />
20 years of experience as a provider of valid<br />
and legally defensible accreditation and certification<br />
examinations <strong>for</strong> professional trade<br />
associations worldwide. We will also <strong>for</strong>ge<br />
long-term relationships with a strong group of<br />
subject matter experts, some of who were<br />
also involved in developing the Occupational<br />
Standards <strong>for</strong> the Accreditation program<br />
earlier this year. This next step promises to be<br />
a lengthy, challenging and yet fulfilling process<br />
— the one we must take to help us reach the<br />
critical milestone to deliver the first GRHC<br />
Accreditation test at our annual conference in<br />
spring of 2009.<br />
SUB-COMMITTEEMEMBERS<br />
Kelly Luckett, St. Louis Metalworks<br />
Roger Schickedantz, William McDonough &<br />
Partners<br />
Jeffrey Bruce, Jeffrey L. Bruce & Company<br />
Stephen Teal, Flynn Canada<br />
Bruce McTavish, McTavish Resource &<br />
Management Consultants<br />
Update by Hazel Farley<br />
Hazel Farley is director, training and accreditation,<br />
<strong>for</strong> <strong>Green</strong> <strong>Roofs</strong> <strong>for</strong> <strong>Healthy</strong> <strong>Cities</strong>.<br />
LIVING ARCHITECTURE MONITOR WINTER
SECTION<br />
ONSPEC<br />
FROMWHEREI<br />
AGREENROOFERSIT<br />
THEROLEOFTHELANDSCAPERONGREENROOFPROJECTS<br />
By Kurt Horvath<br />
On commercial projects it is rare <strong>for</strong> landscapers to participate in<br />
the design process — and that might be OK because not every<br />
landscaper should be a green roof installer.<br />
I have been called in to assess the condition of some green roofs<br />
and have found simple mistakes that have had a huge impact on the<br />
per<strong>for</strong>mance of the green roof.<br />
For instance, on one green roof project we were called into assess, we<br />
found the drainage core was installed upside-down and did not provide<br />
<strong>for</strong> any water retention. For two years this green roof had struggled,<br />
but once the problem was corrected, the roof progressed more in a<br />
single season than it had in the two prior.<br />
A true green roofer is familiar with membrane types, appropriate<br />
assemblies by membrane, plant materials, details, media weights and<br />
general construction practices.<br />
A more complex concern lies in the newness of domestic green<br />
roof design / builds. Many US architects and landscapers lack<br />
experience in specifying green roofs or delivering the best possible<br />
green roof installations. This is why I distinguish myself as a “green<br />
roofer.” The Construction Specifications Institute (CSI) also recognizes<br />
this distinction and even recently assigned green roofs its own<br />
industry code.<br />
Whether you are a landscaper with a growing interest in green roofs,<br />
or another professional part of a green roof team, there is lots to<br />
consider when it comes to the role of the green roof landscaping professional.<br />
Although some of the in<strong>for</strong>mation I have listed below may<br />
be simple and straight<strong>for</strong>ward I still feel it is worth to note:<br />
Number 1, you are on a roof! So it’s safety first. No job is a good job if<br />
someone on your team gets hurt.<br />
Number 2, get educated. Take advantage of the green roof education<br />
courses provided by GRHC and the roofing and waterproofing companies<br />
Number 3, consider and recommend alternatives. Budget constraints<br />
can engineer green roofs out of projects. A true green roofer always<br />
looks <strong>for</strong> ways to conserve. Alternate / hybridized systems can provide<br />
needed savings. Attainability leads to sustainability.<br />
Number 4, manage logistics and think strategically. Installation is the<br />
nitty-gritty, hands-on aspect of the landscaper’s role. Know your systems,<br />
your components, your media and, especially, your plants.<br />
Number 5, follow up. Maintenance, unless otherwise contracted, is the<br />
primary responsibility of the owner who will want to see their green<br />
roofs thriving within the first year of installation. This goal is best<br />
achieved when: the green roof landscaper consults during the design<br />
phase; keeps job costs in line with objectives; respects other trades;<br />
and maintains efficient and safe practices during mobilization and construction<br />
with post-installation follow-up to promote successful growth.<br />
Number 6, help develop your industry and promote green roofs. At<br />
our company, we’re committed to successful outcomes and have a<br />
true passion to build as many green roofs, as cost-effectively, as<br />
green and as fast as possible.<br />
As a landscaper/green roofer, I invite others to envision the same.<br />
The success of each green roof installed will promote the green roof<br />
industry at large — and in this way, we all win. <br />
Kurt Horvath is a <strong>Green</strong> Roofer and the President of Glenview, IL-based<br />
Intrinsic Landscaping, Inc. (www.intrinsiclandscaping.com). Intrinsic has<br />
installed over 100 <strong>Green</strong> <strong>Roofs</strong> in the Midwest. He helped develop<br />
the occupational analysis <strong>for</strong> the Accredited <strong>Green</strong> Roof Professional<br />
designation being developed by GRHC with industry stakeholders.<br />
GOTSOMETHINGTOSAY?<br />
Do you feel strongly about something that is going on in the green roof or wall industry? Do you have a vision <strong>for</strong> how things could be different or<br />
better? Well, stop stewing and start sharing here in our new back-page guest editorial. Send us a 150-word description of what you would like to<br />
write about and you could be featured in an upcoming On Spec. Write to us at editor@greenroofs.org.<br />
<br />
LIVING ARCHITECTURE MONITOR<br />
WINTER