Summer '22

GREENSCAPE 

Ensuring Best Practice for Green Roof & Solar PV Projects MAGAZINE 

SUMMER 2022 

Academic Corner 

Mythbusters! 

Fire Performance 

Safety 

#WGRD2022 Grows Again! 

News, Views & Projects 

Specification Advice 

In collaboration with the Green Roof Organisation

WATERSHED 

MOMENT. 

Meeting Carbon Net Zero and 

the wider challenges of climate 

change needs innovation, vision 

and a fundamental change to 

urban development. 

A breakthrough in water 

management will help 

unlock the solution - Green 

Urbanisation. 

Green Urbanisation 

• Utilises surface water to introduce and sustain urban green assets 

• Promotes biodiversity and ecological regeneration 

• Reduces potable water demand and energy consumption 

• Delivers multi-functional environmental, health and wellbeing benefits 

• Enhances resilience to flooding, drought and population expansion 

Unlock the future at polypipe.com/watershed 

Civils & Green Urbanisation

GREENSCAPE 

IN THIS ISSUE... 

Matt Downs 

Editorial Director 

mattdowns@media-now.co.uk 

07963 330774 

www.greenscapemag.co.uk 

The third instalment of World Green Roof Day took place on June 6th, and if 

anyone still needed convincing of the ever-increasing popularity and importance 

of green roofs, as well as the global appeal and love for these projects, 

#WGRD2022 highlighted all this and so much more! 

The annual event, founded by Chris Bridgman and Dusty Gedge, captured the 

imagination of over 60 countries, with individuals and companies from Brazil to New 

Zealand, and Norway to South Africa getting involved and showcasing the benefits of 

projects of all sizes through video content and in-person rooftop tours, plus people of 

all ages getting creative through the new Lego, Minecraft and poster challenges the 

organisers launched this year! Read more about #WGRD2022 on page 6. 

In his latest Academic Corner column on page 12, Dr Tom Young explains why he believes 

the substrate “is the single most important component of a green roof”, and discusses the 

key considerations you should make to ensure it performs as it should on projects. 

Elsewhere in this issue, Mark Harris, Head of Technical and Operations at Radmat 

Building Products and Chair of GRO, looks at the main guidance and regulations with 

regards to the fire performance of green roofs (page 14); the experts at GRO address the 

misconception that extensive green roofs are self-sufficient in our latest Mythbusters 

column (page 18); Julian Thurbin, MD of Wallbarn, explains why time is of the essence 

when getting products from field to roof (page 22); and with storm events becoming 

increasingly more common, Brian Bell of Marley Alutec discusses best practice when it 

comes to blue roofs (page 28). 

So read on for all this and much more! 

Front cover: Image courtesy of Wallbarn. Julian Thurbin looks at 

the process of getting products from field to roof and explains why 

time is of the essence on page 22. 

GREENSCAPE 

www.greenscapemag.co.uk 

Advertising: 

Publishing Director: Andy Dunn 

DD: 01892 732 047 

Mob: 07963 330777 

Email: andydunn@media-now.co.uk 

Commercial Manager: Jake Roxborough 

DD: 01892 732 047 

Mob: 07956 133314 

Email: jakeroxborough@media-now.co.uk 

Brought to you by the publishers of Total Contractor, the content 

of Greenscape magazine (and website) does not necessarily 

reflect the views of the editor or publishers and are the views of 

its contributors and advertisers. The digital edition may include 

hyperlinks to third-party content, advertising, or websites, 

provided for the sake of convenience and interest. The publishers 

accept no legal responsibility for loss arising from information in 

this publication and do not endorse any advertising or products 

available from external sources. No part of this publication may 

be reproduced or stored in a retrieval system without the written 

consent of the publishers. All rights reserved. 

Registered office: 

1 Forstal Road, Aylesford, 

Kent, ME20 7AU 

Supported by: 

CONTRIBUTORS TO THIS ISSUE... 

This magazine and its packaging can 

be recycled. 

p 12 

Academic Corner 

Dr Tom 

Young of the 

Environmental 

Partnership talks 

substrates. 

p 14 

Fire Safety 

Mark Harris of 

Radmat Building 

Products and 

Chair of GRO looks 

at fire safety. 

p 20 

Correct spec 

Nick Day, 

Managing Director 

of Optigrun 

discusses product 

selection. 

In his latest Academic Corner column, 

Tom looks at the some of the research 

and findings regarding green roof 

substrates, which he feels is the “most 

important component of a green roof.” 

P 12 

In his update on the guidance for fire 

safety on green, blue and biosolar roofs, 

Mark discusses the key considerations 

which need to be taken on board in this 

crucial but tricky area for projects. 

P 14 

Nick explains why with requirements for 

projects becoming increasingly varied, it’s 

vital to ensure the correct products are 

specified for each project to ensure the 

roof performs as it should. 

P 20 

www.greenscapemag.co.uk • GREENSCAPE SUMMER 2022 3

Contents 

NEWS 

6 #WGRD2022: As over 60 

countries got involved with this 

year’s World Green Roof Day, we 

take a look at how people celebrated 

all things green roof around the 

world! 

8 Hot topic: Wallbarn says the fire 

performance of green roofs is a 

crucial consideration in the design 

and specification process 

9 And the winner is... Get involved 

with Green-tech’s new competition! 

GREEN ROOFS 

14 Fire Safety: Mark Harris of Radmat 

and Chair of GRO looks at the key 

requirements and regulations when 

it comes to green roofs and fire 

safety 

20 Specification: Nick Day of 

Optigrun discusses the importance 

of product selection when installing 

green roof systems 

26 Liquid benefits: Victoria Ramwell 

of Kemper System explains why she 

feels liquid waterproofing systems 

are the perfect partner for green 

roofs 

4 GREENSCAPE SUMMER 2022 • www.greenscapemag.co.uk

GREENSCAPE 

SOLAR PV 

30 The proven roofing solution: 

Stuart Nicholson of Marley says 

solar PV ticks a number of boxes 

for homeowners when it comes 

to tackling rising energy costs and 

future demands 

34 Aesthetic appeal and energy 

performance: We take a look at 

the Crest Nelskamp Planum and G10 

S PV integrated solar PV system 

REGULARS 

10 Training: Lantra has launched 

a new e-learning course which 

provides an introduction to green 

roofs for people from all areas of 

expertise 

12 Academic Corner: Dr Tom Young 

looks at the key considerations you 

need to make when it comes to 

green roof substrates 

18 Mythbuster: The experts at GRO 

address the myth that extensive 

green roofs are self sufficient 


News 

GREENSCAPE 

#WGRD2022 REACHES OVER 60 COUNTRIES AS THE POPULARITY OF 

GREEN ROOFS AND ASSOCIATED SYSTEMS CONTINUES TO GROW 

The organisers of World Green 

Roof Day, which took place on 

June 6th, have reported the day 

was a huge success with a number of 

impressive events taking place in cities 

throughout the world. 

Now in its third year, World Green Roof 

Day was founded by green roof experts 

Chris Bridgman and Dusty Gedge, and is 

a global celebration of green roofs, blue 

roofs and biosolar roofs showcasing the 

benefits they bring to people, nature 

and the built environment, with live 

events taking place across the world and 

people getting involved on social media 

sharing images, videos and clips using 

the #WGRD. 

The organisers have stated over 60 

countries celebrated the official World 

Green Roof Day this year, from Brazil 

to New Zealand, and Norway to South 

Africa, as individuals and companies took 

the opportunity to showcase impressive 

green roofs of all sizes, highlighting why 

they love them and their importance to 

their surroundings. 

This year, in addition to the many other 

ways individuals could get involved, 

the organisers put together new fun 

and engaging activities for people of 

all ages, which included providing the 

instructions so children and adults could 

work together to create a Lego green 

roof bus stop; a new Minecraft Challenge 

where individuals could build and 

share their dream green roof using the 

#WGRD2022; plus a downloadable World 

Green Roof Day poster was created for 

people to colour in and share on social 

media. 

Chris Bridgman (pictured 

right presenting), Co- 

Founder of World Green 

Roof Day, explained: 

“These were all fun 

ways for adults and 

children to work together, 

or individually, and engage with World 

Green Roof Day. We’re seeing more 

green roof bus stops appearing in towns 

and cities throughout the UK, so creating 

your own in Lego is a fun way to increase 

awareness of these roadside additions, 

and hopefully help people understand 

that whilst they look pretty, they also 

bring all sorts of additional benefits to 

the area in terms of wildlife habitat and 

sustainability. 

“Likewise, it was great to see what people 

came up with when they created their 

dream green roofs for the Minecraft 

Challenge! Alongside the downloadable 

poster, it was an opportunity to get 

creative, raise the profile of green 

roofs and get more people of all ages 

interested in them.” 

Elsewhere, World Green Roof Day saw 

other key events taking place throughout 

the world, with worldwide participation 

from GRO members and their sister 

companies, including Sempergreen, 

Optigrun, Zinco, Bauder, and BMI Group 

who launched a series of campaign 

videos in 19 different languages, whilst 

green roof federations from around the 

world also brought green roof owners, 

designers, manufacturers and growers 

together to celebrate. 

The Rotterdam Rooftop Walk launched 

the week prior to World Green Roof Day, 

and has enjoyed over 150,000 visitors 

since opening; plus, rooftop tours in 

Israel and Jerusalem are also taking 

place, showcasing the importance of roof 

space for people and nature. 

World Green Roof Day also saw the 

YMCA Milton Keynes launch its new 

green rooftop to its staff and 

residents, supported by MK 

Council, and developer Socius 

also used World Green 

Roof Day to announce their 

proposal for one of the UK’s 

highest biosolar roofs on the 

MK Gateway development. 

The organisers say green roof workshops 

and knowledge sharing also took place 

in Kuwait, and Hungarian green roof 

product manufacturer Diadem delivered 

a construction workshop to 20 building 

and civil engineering professionals from 

Kazakhstan on the day. 

Closer to home, the Rooftop Revolution 

was active on World Green Roof Day 

using #lookup to continue its push to 

unlock the potential of flat roof spaces 

with nature-based solutions implemented 

within all new and retrofit construction 

projects, whilst Ravago released a new 

video focused on the green and blue 

roofs at two newly occupied London 

residential developments – The Forge in 

Upton Park, and Unity Place, part of the 

South Kilburn Regeneration Programme. 

Dakakker – Europe’s largest rooftop farm 

– also celebrated 10 years of growing! 

Looking forward to next year’s event, 

Chris Bridgman explained: “We would 

encourage as many businesses and 

individuals to open up their rooftops to 

the public around the globe to safely 

demonstrate and showcase the multiple 

benefits of roof greening for climate 

action, biodiversity, health and wellbeing. 

Please save the date – 6th June 2023 – 

and celebrate with us!” 

This is just a small taste of what went on 

this World Green Roof Day 2022, find out 

more at www.greenroofs.com or 

www.worldgreenroofday.com 


Proud to be 

a member of 

the GRO Code 

The sky’s the limit 

With a Green Roof System from Green-tech 

1 

2 

3 

4 

5 

1. Choice of soft and hard landscaping 

materials available, including: 

• Sedum Matting 

• gtSedum Cassettes 

• John Chambers Wildflower Matting 

• John Chambers Green Roof 

Wildflower Mix 

• Turf 

• Planters 

2. Intensive or Extensive Green-tree 

Roof Garden Substrate 

3. Drainage Board System, including: 

• Filter Membrane 

• Drainage Layer 

• Rootbarrier 

4. Waterproofing Layer 

5. Roof Structure 

This diagram of a typical green roof construction is for illustrative purposes only to demonstrate the range 

and types of products available for a green roof installation. 

Green-tech is a leading supplier 

of landscaping and green roof 

materials. Our products have been 

used in many high profile and 

award-winning green roof projects 

throughout the UK. 

We can provide everything you 

need for a successful installation, 

including technical advice, project 

specifications, CAD drawings and 

of course, a full range of Green 

Roof products. 

For more information, book a 

free Green Roof System CPD 

presentation, to be delivered 

online or in your office. 

T: 01423 332100 

www.green-tech.co.uk 

sales@green-tech.co.uk 

@greentechltd 

@greentechuk 

green-tech-ltd

News 

BOOST FOR SOLAR AS SOLAR 

SKILLS LONDON EXPANDS 

London’s fast-growing solar sector 

has received a major boost from the 

Mayor this spring with the launch 

of a new online careers hub and 

more financial help for new and 

established solar businesses. 

The online careers hub is a key part 

of Solar Skills London, a skills and 

training programme launched in 

March 2021 by the Mayor of London 

and Solar Energy UK, the leading 

industry body for solar energy and 

storage. 

Solar Skills London has received 

£130,000 from City Hall to create 

more green jobs in the solar energy 

sector which will help towards the 

Mayor’s commitment to achieve 

1.5GW of rooftop solar PV by 2030, 

reducing the capital’s reliance on 

fossil fuels. It will also support his 

ambition for London to become a 

net zero carbon city by the end of 

the decade. 

The online careers hub aims to help 

newcomers map out career paths 

in the solar and renewable energy 

industries. It features job profiles, 

a one-stop shop of the various 

industry standards and qualifications, 

as well as a comprehensive database 

of training courses and colleges. 

The next phase of Solar Skills London 

will also see MCS (Microgeneration 

Certification Scheme) join the 

initiative as a delivery partner. 

WALLBARN: “EVALUATING THE FIRE PERFORMANCE OF LIVING 

ROOFS HAS BECOME INCREASINGLY IMPORTANT” 

Modular green roof specialist 

Wallbarn says the fire performance 

of green roofs is an increasingly 

important consideration during the 

design and specification process. 

The company says it is finding 

that for an increasing number of 

its clients, the issue is given equal 

weight alongside the established key 

considerations of structural loadbearing 

capability and the type of 

green roof required. 

“Evaluating the fire performance of 

living roofs has become increasingly 

important in the post-Grenfell years 

as the fire safety of buildings, their 

components, assembly, construction 

methods and management take 

centre stage,” explained Wallbarn 

Director Julian Thurbin. “It is a 

complex issue influenced by BRE 

requirements, the soon to be updated 

Approved Document B and updated 

guidance from the Green Roof 

Organisation (GRO).” 

physically test it. Wallbarn used an 

independent fire testing authority 

to physically test its M-Tray modular 

green roof system, so says it is 

well placed to advise specifiers and 

installation specialists. 

M-Tray was tested to CEN/TS 

1187, achieving a classification of 

B ROOF t(4) and an EXAP Report 

conforming with CEN/TS 16459:2019. 

Wallbarn believes it is the first 

UK-manufactured green roof to 

achieve this industry standard, and 

furthermore, says its growing medium 

is 100mm thick and contains less 

than 50% organic content, achieving 

compliance to BS 8616:2019. 

“Achieving EXAP Report conformity is 

incredibly important because it allows 

M-Tray to be used in an extended 

range of applications without the 

requirement to test individual 

construction elements when changing 

a specification, for example,” 

concluded Julian. 

Solar installation – 

image courtesy of Marley 

Wallbarn says although a number 

of assumptions on organic content 

and substrate depths are often 

relied upon, the best way to find out 

if a green roof is safe for fire is to 

Wallbarn has produced a white 

paper outlining fire performance 

considerations when specifying green 

roofs. To request a copy e-mail: 

info@wallbarn.com 


GREENSCAPE 

UKGBC REPORT REVEALS THE SIGNIFICANT 

VALUE OF NATURE-BASED SOLUTIONS 

The UK Green Building Council (UKGBC) has launched 

a new framework to support industry recognise and 

capture the significant value and benefit of naturebased 

solutions across urban developments. 

NEW LANDSCAPE COMP! 

Green-tech wants to see your projects 

and is offering you the chance to get 

your latest landscape project in the 

spotlight! 

Between now and 31st August 2022, 

the company is asking you to post a 

picture of your latest landscape project 

tagging @Green-tech, or to email your 

photos to marketing@green-tech. 

co.uk, and you will be entered into a 

competition to win the Green-tech 

Landscape Project Of The Month. 

All entries will be judged by the 

Green-tech team and a project will 

be selected each month. The winning 

project will receive a Champagne Gift 

Set. 

In addition, an overall ‘Grand’ winner 

will be chosen when the competition 

closes and will win two VIP tickets 

to the prestigious BALI National 

Landscape Awards hosted on Friday 

2nd December 2022, along with an 

overnight stay in London. 

Sales Director Richard Gill commented: 

“Green-tech is the headline sponsor 

of the BALI National Landscape 

Awards, and we are delighted to be 

providing 2 free tickets to join us and 

our guests at this prestigious event. 

Tickets are always in high demand 

and the opportunity to join the Greentech 

tables is rare; so, this, along 

with an overnight stay in London, is 

an amazing prize. There are many 

fabulous landscape projects going on 

and we’re looking forward to shining 

the spotlight on a few of them.” 

www.green-tech.co.uk 

UKGBC’s report reveals the scale of positive outcomes 

which Nature-Based Solutions (NBS) can deliver for 

the industry, as well as the wide range of stakeholders 

who can benefit from their implementation across 

cities and urban areas. 

The guidance will support industry to capture and better communicate the true value and 

wide-ranging benefits of NBS, enabling practitioners to develop a stronger business case for 

using NBS and unlock financial opportunities. UKGBC says greater support from the private 

sector will be critical to financing the adaptation gap. 

In February 2022, the Intergovernmental Panel on Climate Change (IPCC)’s reinforced the 

urgent need for climate adaptation, highlighting “any further delay in concerted global 

action will miss a brief and rapidly closing window to secure a liveable future.” Many of the 

risks identified for the UK fall under the direct responsibility of the built environment, such 

as heat stress and flooding. The accelerating impacts of climate change highlight the critical 

need for greater levels of adaptation and mitigation across the built environment. 

UKGBC says NBS offer an adaptation approach for our cities and built environments to 

become more resilient to the impacts of climate change. However, delivering NBS at scale 

will require both public and private funds to be committed at increased levels. To date, the 

majority of global finance for nature has been provided by the public sector, coordinated by 

national and local governments. In the UK a £976 million spending gap has been identified 

for the provision of accessible green (and blue) spaces. Greater support from the private 

sector will therefore be critical to bridging the finance gap for adaptation. 

Launched in May, The Value of Urban Nature Based Solutions, reveals the significant 

scale of benefits that NBS can deliver across developments and communities, as well as 

guidance to support built environment stakeholders to overcome current barriers with 

communicating the true value of NBS. 

This report outlines an approach to successfully integrate NBS into the built environment. 

It includes a suggested framework and a range of innovative mechanisms and examples 

to effectively make the case for and assess the value of NBS. It presents a simple benefits 

analysis approach to help users define the benefits and value that they can draw from 

NBS, supporting them to develop their own business cases for investment, delivery, and 

maintenance of NBS, to further mainstream its consideration across industry. Through 

taking a holistic view of NBS, the approach outlined within the report demonstrates how 

the benefits of NBS can stretch far beyond their primary purpose and can benefit a broader 

range of stakeholders than initially expected. 

It is primarily intended that UKGBC’s guidance will be used by decision makers in the built 

environment, such as developers and asset owners. In addition, members of design teams 

can use this information to support the case for NBS on a project level. This includes 

sustainability consultants, ecologists, and landscape architects. It will also be useful to local 

authorities with an interest in adaptation strategies and green infrastructure. Finally, financial 

institutions such as investors and lenders will find this report useful. www.ukgbc.org 


E-LEARNING COURSE 

NEW E-LEARNING COURSE UNRAVELS THE 

MYSTERIES OF GREEN ROOFING 

“An Introduction to Green Roofing” is a new e-learning cousre from Lantra, and provides 

participants with a good understanding of the green roof industry, enabling them to feel more 

confident in developing their skills through more in-depth and practical training... 

Have you ever wished that you 

had a better understanding 

of green roofs? Perhaps you 

are an architect needing more details 

so that you can bring biodiversity net 

gain into your projects? Or maybe 

you are a roofer who’d like to extend 

your services to installing green roofs? 

Whatever your interest, Lantra’s new 

e-learning course will help you to demystify 

green roofing and develop 

your understanding of the engineering, 

technology and ecology involved in this 

fascinating industry. 

For less than two hours of 

your time, and a very 

modest fee, you’ll be able 

to discover: 

• The background 

behind the modern 

green roof industry. 

• Green roof benefits and 

the many ways that they 

contribute to society. 

Interest in green roofing is growing rapidly and Lantra has introduced a 

new course to help people from different areas of expertise to get a better 

understanding of green roofs. Images courtesy of Chris Bridgman. 

and indeed developers 

and homeowners who 

want to upgrade their 

property by fitting a living 

roof. 

• Different types of green roofs and how 

to decide which is most appropriate for 

your project. 

• Structural considerations when 

designing and specifying green roofs. 

• How to install a green roof – the 

processes used as well as health and 

safety considerations. 

• The importance of ongoing green roof 

maintenance. 

The course, entitled “An Introduction to 

Green Roofing”, is aimed at architects, 

garden designers, roofing contractors, 

trainee green roof installers, planners, 

There are no prerequisites to joining 

and the carefully considered course 

content is presented in easily digestible 

chunks of information. 

At the end of the course, you will have 

a good understanding of the green roof 

industry and feel more confident in 

developing your skills through more indepth 

and practical training. 

Discover more, and sign up via the 

Lantra website at https://www.lantra. 

co.uk/course/introduction-greenroofs-e-learning 

Have you already completed the 

course? Send us a review with your 

feedback to help us improve and 

promote the training content. Email: 

membership@greenrooforganisation. 

org 

Find out more about 

the Lantra course 

https://www.lantra.co.uk/ 

course/introduction–green 

-roofs-e-learning 


SUPERIOR QUALITY SOLUTIONS 

WHATEVER THE APPLICATION 

We provide quality products backed up with the best technical support 

and service levels by employing honesty and integrity in everything we 

do, conscious of the impact our decisions make on our colleagues, our 

customers and with sustainability in mind, the planet. 

www.icbgroup.co.uk

ACADEMIC CORNER 

GREEN ROOF SUBSTRATE COMPOSITION: 

THE IMPORTANCE OF BEING ‘EARNEST’ 

Dr Tom Young looks at the key considerations when it comes to green roof substrates. 

Green roof substrate, also known 

as growing media, is – in my 

opinion – the single most 

important component of a green roof. 

Why? Well, it is because without it you 

would not have any plants, and without 

plants a green roof is, well, just a roof. 

Now, we ask a lot from the green roof 

substrate – according to Ampin et al. 

2010, Friedrich 2008 it needs to be; 

• Lightweight to help reduce 

loading on the roof 

• Free draining and 

aerated to prevent 

excess water build up 

• Able to retain sufficient water to 

support long-term plant growth 

• Contain sufficient nutrition to support 

long-term plant growth, but not 

excessive in order to prevent weed 

growth or unnecessary plant growth 

• Stable to prevent breakdown in the 

long term. 

Purpose blended green roof 

substrates 

A number of companies 

produce purpose 

blended green roof 

substrate. It is important to point 

out that in 99% of cases, a purpose 

made green roof substrate should be 

used (see GRO’s website to see GRO 

approved substrate suppliers). Spoil 

from site workings, or conventional 

topsoil is not appropriate for a green 

roof and its use is strongly discouraged. 

Generally, green roof substrate is made 

from a combination of lightweight 

aggregate (crushed waste virgin brick, 

pumice, heat expanded clay or Lytag), 

coarse sand, green waste compost 

and sometimes other organic sources 

such as coir or wood chippings/fibre. 

Images show examples of green roof 

substrates. Inset: Dr Tom Young. 


As a substrate, moves from extensive 

– shallow between 80-150 mm, more 

drought tolerant green roof – to an 

intensive system – deeper between 150- 

300+ mm – organic content increases 

to reflect the changing requirements of 

the plants (Ampin et al. 2010). 

It should be pointed out, however, that 

not all green roof substrates are the 

same, and should be carefully chosen 

for each specific project depending on 

plant section, substrate depth, irrigation 

provision, aspect, location and climate. 

Substrate composition has a huge 

impact upon plant establishment and 

growth. For example: 

• Increasing substrate organic 

content from 10 to 25% by 

volume increased shoot 

biomass of various grasses 

and forbs by around 

50% under well-watered 

conditions (Nagase and 

Dunnett 2011). 

• Increasing organic content 

from 10% to 50% resulted in a 

115% increase in shoot weight (Nagase 

and Dunnett 2011). 

• The addition of artificial fertiliser 

to Sedum species caused excess 

growth which led to poorer survival 

during drought conditions (Rowe, 

Monterussio and Rugh 2006). 

• Reducing water holding capacity from 

26% to 17% by increasing substrate 

porosity decreased shoot growth of 

grasses by 17%, did not have an impact 

upon root growth, but did increase 

root:shoot ratio by 15% (Young et al. 

2014). 

• The above results were expanded 

upon and drought tolerance examined. 

Reducing initial water holding capacity 

actually improved plant drought tolerance 

by increasing root:shoot ratio and 

preventing excess shoot growth during 

well-watered periods (Young et al. 2015) 

• Different species of plant have 

different optimum 

pH requirements, 

with five different 

Sedum species 

growing best in 

different substrate pH 

ranging from 5.71 to 6.43 

(Zheng and Clark 2013). 

Depth matters 

And please don’t forget the importance 

of depth! There have been numerous 

studies showing that even a small 

increase in depth can have huge 

impacts upon long-term plant 

development and survival (Rowe et 

al. 2006). These include improved 

drought tolerance (Thuring, Berghage 

and Beattie 2006, Olszewski and 

Young 2011), improved frost tolerance 

(Boivin et al. 2011) and improved 

species diversity with heterogenous 

substrate depth across a roof (Bates et 

al. 2015, Heim and Lundholm 2014). 

So, in a nutshell, substrate composition 

(and depth) is extremely important for 

the success of a green roof. There is no 

one size fits all, and substrate should 

be tailored to each individual roof. It 

is always good practice to speak to a 

substrate/green roof expert and ensure 

that the project specification is correct. 

Always ask for up-to-date specification 

sheets from substrate manufacturers 

to assess if the substrate is the correct 

one for the job. There is now a British 

Standard for Green Roof Substrate 

Test Methods (BS 8616:2019) which 

ensures that substrates are all tested 

with the same methodology, regardless 

of laboratory. This makes comparing 

results much easier for the client or 

specifier. Please get in touch with any 

green roof substrate related enquires. 

About the author: 

Tom works for The Environment Partnership (TEP) 

as a Blue-Green Infrastructure Specialist. TEP are a 

multiple disciplinary environmental consultancy with 

specialisms in Landscape Design, management, Ecology 

and Arboriculture. TEP have recently become Associate 

members of GRO and are the first Landscape Architecture 

company to do so. 

Contact 

Dr Tom Young 

E: tomyoung@tep.uk.com 

Tweet: @DrGreenRoof 


FIRE SAFETY 

FIRE PERFORMANCE OF GREEN, 

BLUE AND BIOSOLAR ROOFS 

By Mark Harris, Head of Technical and Operations at 

Radmat Building Products, and Chair of GRO. 

The Building Regulations 

set the Statutory (legal) 

minimum requirements for 

the construction of buildings in the 

United Kingdom, establishing minimum 

performance requirements to prevent 

the loss of life. 

In England, Wales and Northern Ireland, 

the Approved Documents provide 

guidance on how to comply with 

these legal requirements, providing 

individual documents for Structure, 

Fire Safety, Fall Protection, Access 

and Use, Thermal performance, 

Overheating, Glazing, 

Electrical safety, Site 

Preparation, Toxic 

Substances, Ventilation, 

Sanitation, Drainage 

and Heat & Fuel, as well 

as the passage of sound. In Scotland 

this guidance is provided through 

Technical Handbooks. 

Following the tragedy of the 

Grenfell Tower fire on 14th June 

2017, the Building Regulations have 

seen extensive review and update, 

particularly with regards to the fire 

performance of external walls on 

buildings over 18m (11m in Scotland) 

that contain dwellings, with a 

requirement for the external walls to 

be constructed of materials that are 

either ‘non-combustible’ or ‘very 

limited combustibility’ (fire 

class A1 or A2 to BS EN 

13501-1). The same rules 

apply to balconies on 

such buildings. 

The fire performance requirement 

for roofs has not changed since the 

introduction of classifications to BS EN 

13501-5 into the Approved Document 

B in 2006, classifications that relate to 

the BS 476-3 classifications that have 

been in the Approved Document since it 

was introduced in 1965. 

To achieve a fire performance 

classification to either BS EN 13501-5 or 

BS 476-3, testing of a roof construction 

has to be carried out to ENV 1187 by 

an approved fire testing facility. The 

resulting classification report is specific 

to the exact construction tested, so, 

for example, if you carry out a test that 

contains 50mm of PIR insulation, that 

test is not relevant to 150mm of PIR 

Continued on page 16 >>> 

Inset Mark Harris, Head of Technical and Operations 

at Radmat Building Products. Main image: BioSolar 

installation by Radmat in London. 


Liquid Roofing & 

Waterproofing 

KEMPEROL ® 

The first choice 

for liquid membranes 

Long term protection for flat roofs, buildings 

and critical structures 

Warm roofs, inverted roofs, green roofs, podium 

Whatever your requirements, 

we have a certified and proven 

solution to meet your needs. 

Kemperol Liquid Waterproofing 

Contact us to discuss 

With over 60 years’ experience, there’s not many challenges we 

haven’t faced, confronted and overcome. 

Whatever the building, KEMPEROL ® has a range of cold applied, 

root and rot resistant products to suit every green roof 

application. 

visit www.kemperol.co.uk 

To find out more about the KEMPEROL ® range of products 

Tel: 01925 445532 

Email: enquiries@kempersystem.co.uk 

06/4388 

95/3139

FIRE SAFETY 

>>> Continued from page 14 

insulation or any other thickness. The 

same is true for any change to an AVCL, 

adhesive or waterproofing membrane 

change. 

What happens when a Green, Blue 

or BioSolar roof is included? 

Demonstrating compliance with the 

Building Regulations requirements for 

the fire performance of a roof becomes 

even more challenging when you have 

a Green, Blue or BioSolar roof, because 

the approved fire test facilities can only 

test a maximum roof build-up thickness 

of 250mm or 265mm depending on 

test provider. Both warm and inverted 

roof constructions including Green, Blue 

or BioSolar roofs can easily exceed this 

thickness. 

Fortunately, Approved Document 

B references a Department of 

Communities and Local Government 

(DCLG) document published in August 

2013. This document, ‘Fire Performance 

of Green Roofs and Walls’, provides best 

practice guidance for demonstrating 

compliance with the requirements of 

the Building Regulations without the 

need for test by setting ‘Deemed to 

Satisfy’ rules. 

Section 4.5.2 of DCLG ‘Fire Performance 

of Green Roofs and Walls’ states that 

‘In order for green roofs to comply with 

requirement B4 it is recommended that 

for all types of green roof the depth of 

the growing layer should be a minimum 

of 80mm and the organic content 

should not exceed 50%.’ 

Fire breaks 

“Demonstrating 

Inset Mark 

compliance 

Harris, Head 

with 

of Technical 

the 

and Operations 

Building 

at 

Regulations 

Radmat Building 

requirements 

Products. Main image: BioSolar 

for the fire performance 

installation 

of a roof 

by Radmat in London. 

becomes even more challenging when 

you have a Green, Blue or BioSolar 

roof, because the approved fire tests 

can only test a maximum roof build-up 

thickness of 250mm or 265mm 

depending on the test provider.” 

breaks should be installed around all 

openings (rooflights, pipes or vents), 

and vertical elements on all types of 

Green roofs ‘consist of paving slabs or 

non-vegetated strips of pebbles with a 

depth of 75mm and diameter between 

20 and 50mm for a width of 500mm’. It 

goes on to state that ‘It may be possible 

to reduce the dimension of 500mm 

depending on the type of vegetation 

used and the climatic conditions, 

however further investigation and 

evidence would be required to support 

any reduction from the recommended 

500mm fire break.’ 

There is also a statement that ‘Larger 

pebble sizes are preferred as this 

leads to less vegetative growth.’ And a 

recommendation that ‘fire breaks are 

provided in 1m strips every 40m across 

extensive green roofs.’ 

4mm, maximum 32mm), with the UK 

accepting that an aggregate size 20mm 

- 40mm of loose laid gravel falls within 

this CWFT rule due to our wind scour 

requirements. This means that any use 

of a larger diameter gravel as proposed 

in DCLG ‘Fire Performance of Green 

Roofs and Walls’ will require wind uplift 

testing to demonstrate the achievement 

of fire performance requirements. 

When it comes to the size of the gravel 

fire break, the Green Roof Organisation 

provides some guidance that suggests 

the margin width could be reduced 

to 300mm on small green roofs at 

external perimeter walls that do not 

abutt an adjacent building or vertical 

elevation, but that this would need to be 

discussed and agreed with local building 

control officers. 

DCLG ‘Fire Performance of Green Roofs 

and Walls’ also provides guidance on 

the use of fire breaks to support the 

achievement of compliance with the 

Building Regulations, recommending 

the installation of fire breaks to 

prevent the spread of fire into, or 

from, a building on to the Green roof. 

The document recommends that fire 

Parts of this guidance conflicts with 

other guidance, such as Commission 

Decision 2000/553/EC which provides 

Classification Without Further Testing 

(CWFT) rules for surface finishes to 

roofs that include the application 

of loose laid gravel with a thickness 

of at least 50mm or a mass of ≥ 80 

kg/m 2 (minimum aggregate size 

Contact Radmat 

Building Products 

www.radmat.com 

Tweet: @RadmatOfficial 


NEW VIDEO FROM RAVAGO! 

Ravago Building Solutions has 

launched a new video to mark 

World Green Roof Day 2022, 

which provides a compelling behind-thescenes 

glimpse at how Ravatherm XPS 

X insulation is helping the construction 

industry build a greener urban skyline. 

Showcasing the green and blue roofs at 

two newly occupied London residential 

developments – The Forge in Upton Park, 

and Unity Place, part of the South Kilburn 

Regeneration Programme – the video 

captures the process and art behind the 

green roof solution through interviews with 

project contributors, while striking visuals 

cement the approach ‘in reality’. 

Narrators include key figures from Ravago’s 

UK team – Joan Ferrer, Commercial 

Director, UK & Ireland; Richard Powell, 

Roofing Sales Manager; Natalie Sutton, 

Account Manager (South of England); and 

James Curson, Reliability & Productivity 

Specialist – as well as collaborators at longstanding 

partner Radmat Building Products: 

Area Technical Manager, Michael Fadian, 

and Head of Technical and Operations, 

Mark Harris, in his capacity as Chair of the 

Green Roof Organisation (GRO). 

Aerial footage of both projects is 

interspersed with a high-speed drone tour 

of the King’s Lynn plant that produced the 

Ravatherm XPS X extruded polystyrene 

insulation boards used to construct both 

roofs, and where Ravago began making 

the UK’s first-ever range of XPS insulation 

products over 60 years ago. 

Joan Ferrer said: “Our rapidly changing 

world requires that we adapt how we live, 

work, and build. With a proud legacy in the 

UK construction market, but a mentality 

of looking ahead to the future, Ravago 

has been able to adapt to these many 

Above: Unity Place, part of the South Kilburn Regeneration 

Programme features in the video. 

new demands throughout its history 

and delights in helping customers meet 

challenging specifications with innovative 

solutions. Green and blue roofs, such 

as at The Forge and Unity Place, are an 

important tool in creating more resilient 

and people-centred cities, creating visually 

attractive and usable space that contributes 

to biodiversity and mitigates flood risk. By 

launching this new video on World Green 

Roof Day 2022, we hope to offer a fresh 

perspective of the possibilities in urban 

construction, and ultimately contribute 

greater momentum to the green roof 

movement.” 

View the video here: 

https://youtu.be/RQEHnR_TftU 

We’ll bring your 

roof to life! 

GREENING 

ROOFTOPS 

ANY SIZE 

ANY SYSTEM 

ANYWHERE! 

www.gardensinthesky.co.uk

GREEN ROOF MYTHBUSTERS 

MYTH: EXTENSIVE GREEN ROOFS 

ARE SELF SUFFICIENT 

Truth: As the experts at GRO explain, ALL living roofs need maintenance, but extensive green 

roofs are relatively easier to care for than intensive green roofs. 

Because extensive green roofs 

don’t have the same manicured 

appearance as intensive green 

roofs, it’s easy to assume that they are 

semi-wild places, adopted by nature 

because they are largely undisturbed by 

human activity. 

It’s true, extensive green roofs are not 

designed to be managed like gardens. 

But it’s also true that most wild scapes 

at ground level are subtly, yet carefully 

managed. A combination of grazing 

animals and mechanical means ensures 

that the plant cover is not overwhelmed 

by scrub and then woodland. Think 

of sheep on the moors, wild ponies in 

the New Forest or cattle on wetland 

meadows, they’re not there for 

decoration or for profit – they manage 

the landscape. 

Of course, keeping native ponies, sheep 

or cattle on your living roof is not a 

practical option. And so green guardians 

need to replicate the effects of their 

actions by implementing a green roof 

maintenance regime, lest their roof 

become unmanageable and ineffective. 

Maintaining the benefits of a 

living roof 

Most of the benefits of a living roof are 

afforded by the vegetative layer. The deep 

substrate that supports plant growth also 

helps with stormwater management. 

Thermodynamic benefits are supplied 

partly by the substrate and partly by the 

actions of plants. Evapotranspiration from 

living plants helps to cool the air, whilst 

air trapped beneath the plants acts as 

a blanket to help insulate the building 

against heat and cold. 

Biodiversity net gain is also provided by 

vegetation. Not just through the mix of 

plant species on the roof but through the 

food and shelter they provide to a wide 

range of birds and insects. However – 

allowing unwanted plants to colonise the 

structure could lead to desirable plants 

being outcompeted. Or worse – rampant 

roots of shrubs and trees could damage 

the waterproofing. That would be an 

Leeds Skelton Lake Motorway Services. 

Image credit ABG Geosynthetics. Right: The Ikea 

Green Roof, Greenwich. Image credit Bridgman & 

Bridgman Landscapes. 


expensive problem to rectify! 

It follows therefore, that keeping the 

vegetative layer of a green roof in 

good condition is key to maintaining or 

even enhancing that roof’s benefits to 

humankind. 

What is involved in maintaining an 

extensive green roof? 

• Maintaining the structural features that 

influence green roof performance such 

as drainage outlets and irrigation systems 

• Regular testing of fall restraints 

• Removing debris and unwanted plant 

material 

• Fertilisation - although this does not 

apply to all living roofs 

• Managing the balance of species 

growing on the roof 

Each living roof will of course be slightly 

different in its maintenance requirements, 

and ideally, care will be taken to plan and 

budget for maintenance at the design 

stage. However, the basic principles are 

very similar for any and every extensive 

living roof. 

Maintaining an extensive green roof 

should have a two pronged approach. 

First, it’s vital that the green roof 

infrastructure is maintained. This, after 

all, is what creates the plants’ living 

conditions. Drought loving plants will not 

survive on a soggy roof any more than 

they would in a terrestrial bog garden. 

Secondly, the needs of the plants must 

be met. Removing the competition from 

unwanted plants and ensuring that 

desirable plants have everything they 

need in order to thrive is key to a healthy 

living roof. Understanding which green 

roof systems need extra support through 

fertilisation is an art form in itself. Your 

installer should give you some guidance, 

but as a rule of thumb, extensive green 

roofs with a good depth of substrate and 

a population of wildflowers need fewer 

additional nutrients than a sedum roof. 

How often are 

maintenance visits 

required? 

For best 

practice, an 

established 

extensive 

living roof 

should have 

at least two 

maintenance 

visits per 

year. Ideally, 

one in the spring 

to check that 

plants are recovering 

well from the winter and 

that drainage outlets are fully 

functional. And a further visit in autumn 

to clear debris and unwanted plant 

material. 

For a recently installed living roof, 

the Green Roof Organisation (GRO) 

recommends that the installing 

contractor take responsibility for it during 

the establishment stage. 

Is green roof maintenance 

expensive? 

A better question would be “what 

is the cost of neglecting green roof 

maintenance?” Just like any other 

housekeeping tasks, there will be a cost 

to green roof maintenance. However, 

Granny always said that ‘a stitch in time 

saves nine’ and she was right. The cost 

of removing a forest of young trees 

from your green roof and then repairing 

root damage to your waterproofing 

far outweighs the cost of regular 

maintenance visits. 

If you think of green roof maintenance 

as an investment (or an insurance) rather 

than a cost, it doesn’t seem expensive at 

all. After all, would you buy an expensive 

car and never service it? 

Aside from the environmental and 

architectural value of a living roof, the PR 

opportunities are immense but all three 

of those benefits could be jeopardised 

by an inadequate 

maintenance regime. 

Regular 

green roof 

maintenance 

anticipates 

and 

negates 

any 

possible 

issues, and 

just like 

any good 

housekeeping 

is a more cost 

effective way of 

managing the needs of 

the building and the ecosystem 

it supports than waiting until something 

goes wrong. 

Does green roof maintenance require 

special training? 

Green roofing, as an industry is unique. 

Anybody designing or maintaining a 

living roof needs a good understanding 

of the engineering and technology 

that supports the vegetation. At the 

same time, they also need a thorough 

knowledge of horticulture and ecology. 

Green roof maintenance is not a job 

for a gardener, nor for a roofer, but for 

someone whose skills set spans the 

two industries. Specialist training can 

be arranged through GRO or Lantra. 

For more information, visit https:// 

greenrooforganisation.org/green-rooftraining/ 

You will also find a wealth of information 

about green roof maintenance 

in the GRO Green Roof Code. 

Download it for free from https:// 

greenrooforganisation.org/downloads 

Contact 

GRO 

www.greenrooforganisation.org 

Tweet: @RoofGro 


GREEN ROOFS SPEC ADVICE 

GETTING THE SPECIFICATION RIGHT 

Nick Day, Managing Director of green roof specialist Optigrun, discusses the importance of 

selecting the right products when implementing green roof systems. 

The benefits of green roofs are 

now widely recognised, and they 

are becoming a familiar inclusion 

on building developments, with the 

requirements of specifiers when it comes 

to roof greening increasingly varied. 

As with other parts of the building 

fabric, it is important for the green roof 

specification to be correct to ensure 

long-term performance. Whether the 

goal is to increase biodiversity, manage 

rainfall or improve air quality, it’s 

important to select the right products 

and systems and to remember that 

there’s no “one size fits all” when it 

comes to green roofs. 

This article examines some areas of 

the green roof build-up where correct 

product selection is vitally important so 

that subsequent performance 

issues can be avoided. 

System approach 

At Optigrun we have 

nearly 50 years’ 

worth of experience 

developing green roof 

products and systems, 

and regularly advise 

specifiers and contractors 

regarding specification and roof 

design. We have found that the system 

approach to product choice works best 

using a combination of layers that have 

been developed and tested to work 

together in the same way that the 

waterproofing and insulation system 

beneath the green roof will have been. 

The green roof system chosen needs 

Left: Nick Day, MD at Optigrun. 

to reflect the type of 

vegetation that will be 

required, the level of 

water storage required 

and the type of use that 

the roof will receive. 

Within each green roof 

system there are key 

product areas that need to be 

considered. 

Drainage layers 

Every vegetated green roof needs a 

reservoir function to store water for 

irrigation purposes during extended 

dry periods, but also good drainage. 

Poor drainage provision can risk 

waterlogging of the substrate layer with 

Left: Illustration shows a green roof 

build-up. Below: Illustration shows an 

Optigrun green roof layout. All images 

courtesy of Optigrun Ltd. 


Optigrun FKD 25 drainage board - for use on 

standard sedum roof system build-up. 

consequent root damage and potential 

failure of the vegetation. A good green 

roof system will provide this at different 

layers within the roof make up, one of 

which is within the drainage layers. 

The drainage layers on a vegetated 

green roof will typically consist of a 

protection fleece – unless the roof 

is of an inverted design – drainage 

and reservoir board and filter layer. 

With regard to the drainage and 

reservoir board, this will typically be 

manufactured from a recycled plastic, 

and it’s important that it has good 

reservoir function on its upper face with 

individual storage cells or chambers 

with overflow provision so that excess 

water can drain away below the board. 

The underside of the board should 

facilitate good drainage so that water 

cannot back up through the board and 

risk waterlogging of the substrate layer 

above. For example, at Optigrun we 

have different drainage and reservoir 

boards within our systems, ranging 

from 20mm to 60mm in depth, with 

different performance characteristics 

so that the correct product can be 

chosen for each project. The filter 

fleece that’s laid above it should have 

good mechanical filtration properties 

but also allow a sufficient rate of 

water flow. The current Green Roof 

Organisation (GRO) Green Roof Code 

(2021) sets out minimum performance 

characteristics for this layer. 

Pitched roofs 

Pitched green roofs are being specified 

in ever greater numbers and these 

present their own set of requirements 

when it comes to product selection. The 

general rule here is that it’s best not to 

improvise with the specification, but 

instead to use a system designed for 

the purpose. The “system approach”, 

mentioned previously, definitely 

applies where pitched green roofs are 

concerned. 

Generally, a pitched green roof is 

considered to be one that has a pitch 

in excess of 5 degrees. Beyond this 

figure the green roof specification will 

need to be completely different as the 

physics of the roof change. For example, 

transferred shear load and slippage risk 

have to be considered and the method 

of accommodating this will vary on 

each roof depending on, for example, 

pitch, slope length, waterproofing 

membrane being used and roof design 

– i.e., mono or duo pitch, perimeter 

detailing etc. The method of providing 

water storage and drainage will also 

change. I have surveyed several failed 

pitched green roofs in the past where 

an improvised anti-slip arrangement 

has been used, or in one case none at 

all, creating costly mistakes which could 

have been avoided if the correct system 

had been selected originally 

For pitched green roofs, therefore, 

a range of solutions is needed, and 

an engineered solution is required to 

provide a bespoke specification suited 

to the individual project. 

Substrate 

For the substrate or growing medium 

for a green roof, topsoil or recovered 

site spoil are not suitable products. 

Instead, a blended and engineered soil 

replacement should be used with a 

specified organic content. In this way 

the performance characteristics of the 

material, such as weight, water storage 

capacity, organic content and porosity 

are known. 

The GRO Green Roof Code sets out 

performance characteristics and also 

recommends that substrates selected 

Optigrun substrates are specifically 

engineered to provide the correct organic 

content needed for each green roof system. 

should have been tested according 

to BS 8616:2019 Specification for 

performance parameters and test 

methods for green roof substrates. 

Technical support 

Finally, it may seem obvious but make 

use of the technical services that 

your green roof supplier provides. 

They should be able to provide a 

bespoke specification for your project 

which should include technical data 

for the products included. If you are 

a contractor tendering for a green 

roof, this is particularly important as 

the specification that came with the 

enquiry may have been cut and pasted 

from a previous project and be entirely 

unsuitable for the project in hand. 

There is also useful independent advice 

available from GRO who are the body 

that represents the green roof industry 

in the UK. The latest edition of the 

Green Roof Code, introduced in 2021, 

and mentioned in this article, is full of 

useful information and design guidance 

for green roofs. You can download a 

free copy at: 

www.greenrooforganisation.org 

Contact 

Optigrun 

W: www.optigruen.com 

E: info@optigreen.co.uk 

T: 0207 5899 400 


MODULAR SYSTEMS 

FROM FIELD TO ROOF 

As Julian Thurbin, MD of Wallbarn explains, the time from when the materials arrive on site, through 

to installation, is precious. Below, he points out some of the key considerations to make, and explains 

how Wallbarn works to ensure its M-Tray modular system makes things easy on projects. 

When specifying green roofs, 

it’s easy to forget that they 

are living, breathing mini 

eco-systems that require special 

consideration to ensure they arrive 

on site in pristine condition and are 

installed as quickly as possible to deliver 

a successful outcome. 

Given they are the only living element 

of a new-build or retrofit building 

project, we don’t feel it is unreasonable 

that the proverbial red carpet be 

rolled out for their arrival on site, with 

all involved in accepting the delivery, 

temporarily storing and then installing 

the system, made fully aware of its 

arrival and the applicable window of 

installation time. 

Below: Aerial shot of the Wallbarn nurseries; 

hydroseeding; and tray laying (below right) 

Taking this approach should ensure 

that the green roof is stored correctly 

if not being laid immediately. This is 

vital to prevent the plants ‘steaming’ – 

where enzymes, naturally occurring in 

the plants, heat up and break down the 

leaves, causing irreversible damage to 

the green roof and wreaking havoc with 

a project. 

We always advise that any green roof 

delivery should not remain stacked or 

rolled for more than 48 hours, which 

for Wallbarn and our M-Tray modular 

system is rarely a problem 

given we can have 

our UK designed, 

developed 

and grown 

system 

from field 

to roof 

within just 24 hours. 

This has a number of advantages as the 

demand for green infrastructure grows, 

not least that plants arrive on site in 

pristine condition, giving the green roof 

the best start possible. Quick delivery 

also means that late changes to a 

building design to incorporate a green 

roof can, if required, be achieved with 

M-Tray. 

Planting & growing 

All M-Trays begin their life at our 

nursery in Hampshire, where the 

500mm x 500mm polypropylene 

trays are laid out in growing beds 

ready to be filled with substrate and 

hydroseeded. 

We’ve automated the tray laying 



SAVVY SHOPPER 

THIS AWARD IS PRESENTED TO THE: 

Laura Crombie 

Brand Director 

Real Homes 

M-Tray®: modular, instant green roofs 

EASY ON EASY OFF 

The great outdoors 

WALLBARN M-TRAY 

M-Tray 

installed by 

YMCA 

students on 

the awardwinning 

Green Roof 

Project, 

Milton 

Keynes. 

www.wallbarn.com 0208 916 2222 

has your green roof been physically 

FIRE TESTED? 

M-Tray® has to B ROOF (t4) 

British grown - quick delivery - easy installation - all-year vegetation

MODULAR SYSTEMS 


process by designing a bespoke unit 

that is towed behind a tractor which 

efficiently slides trays off three abreast 

in long, straight lines. The compost 

spreader follows, evenly filling the 

trays from a conveyor belt (with a little 

overfill to allow for settlement) before a 

levelling box passes over to gently press 

the substrate down to create an even 

surface ready for seeding. 

Because sedum seeds are incredibly 

small and even distribution into the 

substrate is not easy, we’ve developed a 

hydroseeding system where the seeds 

are mixed with water and released with 

an agricultural spinning disc dispenser. 

This gives an even distribution and 

helps the seeds sink a little into the 

substrate to start the germination 

process. The irrigated plants are then 

left to grow and mature for up to 12 

months, assisted by regular feeding, 

weeding and close control of quality. 

With no ‘hot housing’ to accelerate 

growth they produce strong roots, are 

fully integrated into the substrate and 

hardened to the elements. 

Harvesting 

Because Wallbarn designed and 

developed the B ROOF t(4) compliant 

M-Tray system, we’ve also had to design 

and build our own harvesting machines 

to maintain an efficient and careful 

system to lift established trays from the 

field. This self-propelled machine has 

specially designed wedges and spokes 

to lift trays off the ground and separate 

them, drawing them up a conveyor 

belt ramp to a processing platform. 

Operatives check the M-Trays for quality 

and palletise them in the field. Trays 

picked today are on site tomorrow. 

Substrate science 

Wallbarn is at the forefront of 

developments in the green roofing 

sector and has always provided 

products that combine top quality 

ingredients with user friendly, hassle- 

Wallbarn has designed its own harvesting machines to maintain an efficient and careful system to 

lift established trays from the field. The M-Trays are checked for quality and palletised in the field. 

free maintenance. Each element of 

M-Tray has been carefully considered, 

from the design of the tray to the 

scientifically developed substrate and 

selection of sedum and wildflower 

plants. 

Working with an independent soil 

specialist, we’ve developed bespoke 

substrate mixes that comply with 

BS 8616:2019 Specification for 

performance parameters and test 

methods for green roof substrates, 

and with the GRO Code. They are our 

own tried-and-tested recipes using raw 

materials that are recycled and come 

from local sources where possible. 

Crucially they have been physically fire 

tested and comply fully with the latest 

fire safety regulations. The three key 

substrate ingredients are: 

• Coir, or recycled coconut fibre, which 

holds moisture and nutrients and has 

good drainage properties. It has high 

lignin content and is relatively resistant 

to slumping, providing long-term 

sustenance to the plants. 

• Lightweight mineral aggregate is 

the main component of the substrate, 

giving free drainage and improved 

rooting conditions. We use a variety 

of different aggregates with different 

particle sizes, including Lytag and 

expanded clay balls (Lecca). 

• Locally sourced organic compost 

which provides water absorption whilst 

slowly releasing nutrients. 

We do not use brick dust or building 

rubble as these can form a crust within 

the substrate, causing blockages and 

poor rooting. Nor do we use peat or 

construction waste. We are constantly 

trialling and developing new mixes 

to provide our customers with the 

optimum substrate, including super 

lightweight modular green roofs and 

carbon negative mixes. 

Contact Wallbarn 

www.wallbarn.com 

T: 020 8916 2222 

@wallbarn 


GREEN ROOF BUILD-UPS 

GOING GREEN WITH LIQUID 

WATERPROOFING 

Victoria Ramwell, from cold applied liquid waterproofing specialist Kemper System, explains why 

she feels liquids are the perfect partner for green roof applications. 

The green roof market in the 

UK is still growing, and it enjoys 

a healthy trajectory thanks to 

sustainability agendas as well as an array 

of planning and environmental policies 

which are pushing for green elements to 

be included in most new-build projects. 

Where the market was once very much 

centred around London, now you will see 

green roof specification on buildings up 

and down the country. 

We all know that correct waterproofing 

specification and installation is vital 

when it comes to green roof design. 

The waterproofing membrane is a key 

element of the specification. If installed 

according to manufacturer instructions 

and training, liquid waterproofing 

guarantees a watertight barrier between 

the roof substrate and the green roof 

system, and it is also root resistant. 

Liquid waterproofing specification 

Liquid waterproofing systems provide one 

of the most long-term and cost-effective 

solutions for a green roof system. 

Correctly installed and maintained, they 

can provide a durable and robust solution, 

often in excess of 20 years with the 

correct British Board of Agrément (BBA) 

certification. 

By their seamless nature, root resistant 

grades of liquid applied waterproofing 

systems are ideally suited for use in green 

roofs without the need for a separate 

root resistant layer. 

Suitable for both warm and inverted roof 

installations, liquid waterproofing systems 

should be BBA certified for green roof 

applications, with the installer ensuring 

the correct grade of product is being 

applied. 

Guidance from the Liquid Roofing and 

Waterproofing Association (LRWA) says 

the growing medium used above the 

drainage board should be a suitable 

depth to support the desired plant life 

and, if an inverted roof, it must provide 

the minimum 80kg/m 2 loading required 

to prevent both floatation and wind uplift

of the insulation. 

Installing liquid waterproofing means 

the membranes are fully bonded to the 

substrate. In addition, when detailed 

correctly, they are able to withstand 

building movement well in excess of 

standard tolerances. 

Design stage considerations 

Plants must be agreed from the outset 

as the roof will need to be designed 

accordingly. For example, wildflower 

meadows are a popular choice for large 

roof surfaces, but they need plenty 

of moisture, which means designing 

the roof to accommodate the load 

and providing a deeper reservoir core. 

Alpine planting, however, needs much 

less water to thrive so this will have less 

of an effect on the roof’s load bearing 

requirements, but will still need to be 

considered. 

Is it also vital that location and prevailing 

climatic conditions are considered 

as these govern the amount of light, 

heat, shade and moisture the roof will 

receive. Surrounding buildings, which can 

influence shade and exposure to winds, 

should be taken into account. These 

factors must be assessed collectively to 

determine the viability of different types 

of planting. 

Installation considerations 

When installing the liquid waterproofing 

system, it is important that the detailing 

such as upstands, pipe penetrations 

and rooflights are designed to take into 

account the increased build-up of the 

green roof construction. 

Building Regulations typically require 

the waterproofing detailing to finish 

150mm above the finished roof surface, 

which in this case would be the green 

roof surface and not the surface of the 

waterproofing. 

In addition, a contractor must ensure 

they deliver correct attenuation and 

drainage systems in accordance to the 

specification to ensure the plant on 

Kemper System has been involved with a number of green roof projects throughout the UK. 

the green roof is cared for. It’s essential 

that not only the contractor, but the 

end client is aware of the maintenance 

requirements for the green roof after 

installation. If this is not addressed, it 

could still be within the retention period 

of the contractor and responsibility 

could fall on them should there be any 

issues. It’s always worth checking this 

in advance to ensure contractors are 

protected. 

A watertight solution 

The effectiveness of the waterproofing 

membrane between the roof substrate 

and the green roof system is the most 

vital element of the specification. The 

membrane should be flexible enough 

to cope with any post-build settlement, 

durable enough to cope with the 

planting’s load bearing requirements and 

have a sufficiently long service life to 

make the green roof viable. 

A common green roof design would 

typically consist of an inverted warm roof 

build-up with the waterproofing system 

applied to the roof substrate, followed 

by the insulation, and then the green 

roof elements. This can add an extra 

layer of protection for the waterproofing 

membrane as it is cushioned underneath 

the insulation. 

However, a liquid waterproofing 

solution such as Kemperol V210 or 

Kemperol 2K-PUR can be cold applied 

either below or above the insulation, 

depending on the type of insulation 

used. These systems are FLL certified 

as root resistant, so there is no risk 

of damage even as plants mature. 

Kemperol 2K-PUR is also odourless, 

adding to its green credentials. 

Alternatively, Kempergro from Kemper 

System combines recycled, renewable 

and sustainable components to provide 

a complete waterproof roofing and 

green roof system from a single source 

supplier. 

Specialist advice 

Whether you’re planning a green 

roof for a city centre building or 

family home, seek technical advice 

from waterproofing and green roof 

specialists. Their knowledge will 

ensure your green roof performs to 

the required specification, meeting 

climatic, aesthetic and biodiversity 

requirements. 

Contact 

Kemper System 

W: www.kemperol.co.uk 

T: 01925 445532 


BLUE ROOFS COMMENT 

SUSTAINABLE DRAINAGE SYSTEMS 

& BLUE ROOFS 

With severe storm events becoming increasingly common, the wider use of blue roofs as part of a 

Sustainable Drainage System (SuDS) strategy will be crucial for the control of rainwater and flood 

mitigation. Brian Bell, Head of Technical Services at Marley Alutec, provides an overview of the system, 

the NFRC’s guidance and what to consider in terms of outlets, drainage and emergency overflows. 

For urban areas, flooding is a 

significant issue due to the 

increased number of hard 

impermeable surfaces. The impact of 

climate change will intensify this issue, with 

statistics showing that extreme weather is 

becoming increasingly common in the UK. 

In fact, a Met Office study found that it is 

now seven times more likely for extreme 

winter rainfall to take place. 

Therefore, rainwater solutions must 

be implemented to address the risk 

of flooding from urban runoff. SuDS 

were developed to manage 

stormwater as close to 

its source as possible, 

replicate natural drainage 

and encourage infiltration, 

attenuation and passive 

treatment. The Flood and 

Water Management Act 

2010 requires residential and 

commercial developments to utilise 

SuDS to reduce the risk of flooding. 

The use of a blue roof is one way that 

a SuDS strategy can be adopted. This 

Brian Bell, Head of Technical Services at 

Marley Alutec. 

is typically designed as 

a flat roof system and 

built to temporarily store 

and release rainfall at a 

controlled rate. However, 

as there isn’t currently 

a national standard for 

blue roof systems, the National 

Federation of Roofing Contractors’ 

(NFRC) ‘Technical Guidance Note for 

the Construction and Design of Blue 

Roofs’ should be used for guidance. 

This image: Marley Alutec blue roof illustration. 


The key feature of a blue roof is an 

attenuation void in which water can 

be contained. This is positioned above 

a waterproof membrane in a warm 

roof design and above the water flow 

reducing layer on an inverted roof. 

Blue roofs are also often combined 

with green roofs due to the need for a 

permeable roof surface to capture the 

water. 

When designing a blue roof, optimum 

drainage and discharge should be 

achieved for effective stormwater 

attenuation to take place. Establishing 

the site drainage rate and storage 

volume capacity are key factors for this. 

The overall site drainage rate, set by 

the planning authority, is often defined 

as the ‘greenfield runoff rate’ and is 

the rate of discharge if the land was 

undeveloped. Typically, this is between 5 

to 8 litres per second per hectare. 

The storage volume is how much 

rainfall the site can hold and then 

discharge. The standard commonly set 

for SuDS is the ability to attenuate a 

storm event with a return period of 1 in 

100 years, meaning a storm intensity 

with an annual probability of 1%. 

However, the location of the site and 

type of development may also affect 

this calculation. 

In addition, the site must be viewed 

holistically as the maximum storage 

volume will also often be influenced by 

the size of the roof area and the roof’s 

loading capacity. The NFRC guidance 

states that for a void depth of 100mm, 

the water can exert an additional load 

of 1.0kN/m 2 on the roof structure, which 

must be accounted for. 

Number and position of outlets 

The NFRC guidance also highlights 

that stored water should be discharged 

within 24 hours of rainfall. Therefore, 

the number and position of roof outlets 

should be calculated to ensure effective 

drainage and achieve the required run 

off rate. Some blue roof outlets, such 

as Marley Alutec’s Elite outlets, feature 

adjustable flow restrictors, allowing the 

outlets to deliver various runoff rates 

and water depths to meet whatever the 

required rate might be – whether that’s 

from 0.35 to 5.58 litres per second (l/s) 

at 25 mm water depth to 0.58 to 9.31 

l/s at 150mm depth. Only high-quality 

outlets should be selected due to their 

necessary exposure to high water 

pressure for extended periods of time. 

Marine grade aluminium outlets offer 

specifiers increased natural strength, 

corrosion resistance and overall 

longevity. 

The outlet and roof structure should 

also have a secure connection. 

Marley Alutec’s Elite outlets feature a 

membrane compression clamp and 

high performance butyl sealing ring 

to ensure a durable, watertight seal. It 

is recommended to use products that 

have been tested beyond the predicted 

requirements to guarantee that 

unexpected conditions will not lead to a 

system failure. 

Finally, the discharge of excess water 

should be considered. If overloaded, a 

blue roof can cause water ingress that 

will damage the roof structure and 

building. To combat this, outlets can 

The range of Elite Outlets from Marley Alutec. 

be used to facilitate emergency water 

discharge by integrating an overflow 

into the outlet. However, measures 

to prevent debris blocking the outlet 

should also be considered and regular 

inspections should be carried out to 

ensure the system is operating as 

intended. 

Blue roofs are an effective way to 

mitigate flooding in urban areas. With 

the increased likelihood of severe 

flooding in the coming years, there 

are manufacturers that can provide 

key technical support for specifying 

drainage designs. These manufacturers 

can also align with wider environmental 

aims through responsible sourcing and 

accreditations such as ISO 14001 for 

environmental management. 

Find out more about 

Marley Alutec 

www.marleyalutec.co.uk/ 

Tel: 01234 344108 


SOLAR PV RESIDENTIAL 

SOLAR PV: THE PROVEN ROOFING SOLUTION 

FOR SUSTAINABLE AND LOWER COST ENERGY 

Stuart Nicholson, Roof Systems Director at Marley, says the specification and installation of solar 

PV on roofscapes can help create greener homes, ensure new houses meet low carbon regulations 

and provide access to renewable energy sources for homeowners concerned about rising energy 

costs – plus, he says its inclusion will also attract consumers looking to buy new houses that come 

with designed-in sustainable solutions... 

More than ever, how we plan 

for and construct the nation’s 

homes is reaching a state 

of critical importance. The escalating 

climate crisis, reinforced at last year’s 

COP26 conference, together with 

unprecedented surges in energy costs, 

means Government policy and consumer 

behaviour is driving demand for low 

carbon housing, along with a desire for 

greener and cheaper energy sources 

within the home. 

Left: Stuart Nicholson, Marley. 

Below and next page: Marley 

SolarTile. 

Part L of the Building 

Regulations is 

designed to ensure the 

building of more energy 

efficient, low carbon and 

sustainable homes. This 

is an interim measure before 

the Future Homes Standard becomes 

a reality in three years’ time. The shortterm 

objective is to ensure 

the construction of new 

homes produces 31% lower 

carbon emissions. 

Builders also need to carefully consider 

how they respond to a changing 

consumer landscape fuelled by energy 

economics and radical changes to 

working patterns caused by the 

pandemic. Fully aware that future buyers 

will have energy efficiency and working 

from home as key priorities, the sector 

needs to ensure such considerations 

are met, and the functionality of future 

housing stock continues to match 

consumer expectations. 

The role of solar as a strategic 

product answer 

Housebuilders who take a strategic view 

on the positive contribution roofing can 

make towards the delivery of sustainable 

homes, will be well positioned to 

match these strategies with changing 

consumer lifestyles, energy cost 

pressures and Government low carbon 

policies and regulation. 

Experts say the immediate improvements 

required in new home energy efficiency 

cannot simply be delivered by enhancing 

building fabric alone. The expected route 

favoured by housebuilders will see the 

specification of solar PV on the roof, 

alongside an efficient gas boiler, or a 



Technical support 

Roofing experts on-hand to offer help and advice 

Assured standards 

Meets all British Standards and regulations 

High-quality components 

Tested for maximum performance, meaning no call backs 

Estimates & fixing specs on demand 

We’ll help you create them on site and on the go 

Comprehensive roof solution 

Easy installation with tried and tested compatible components 

Need a complete 

roof system? 

We’ve got you covered. 

With all elements brought together from a single 

source, you can be confident that everything 

will work together perfectly – and that high 

performance is all backed up with a 15-year 

system guarantee. Find your peace of mind. 

marley.co.uk/roofsystem



heat pump, to achieve the required levels 

stipulated by the Part L changes. 

Seamless integration 

The latest and fully integrated solar 

PV roof systems offer a more visually 

appealing, cost efficient and easy to install 

option. The integration benefits mean 

solar panels can simply replace a section 

of existing roof tiles to create a sleek 

aesthetic and deliver a seamless solution 

as part of the roof’s overall visual appeal. 

Solar PV technology is tried and tested, 

readily available and has become much 

more affordable in recent times, making it 

a highly attractive solution. Indeed, Solar 

Energy UK predicts that the modification 

to Part L could lead to a five-fold increase 

in the number of new homes built with 

solar technology as part of long-term 

sustainable construction strategies. 

Roofing design that optimises solar 

benefits 

As part of overall roof design planning 

and implementation on new builds, 

optimising the energy generation cost 

efficiencies that solar provides should 

also be considered. 

Housing developments that use solar 

PV solutions should focus on capturing 

as much sun as possible to maximise 

the benefit for low carbon and low-cost 

energy generation. This translates into 

ensuring properties have south facing 

roofscapes and the avoidance, if possible, 

of shadows emanating from surrounding 

trees, buildings, and other means nearby. 

In addition, new property design should 

look to incorporate larger scale roof 

spaces so increased solar panel volumes 

can be integrated onto to deliver 

optimum low-cost energy generation 

benefit. The seamless installation of solar 

PV as part of an integrated full roofing 

solution not only guarantees access 

to cheap energy, but it also provides 

a stylish finish that negates prevailing 

concerns about the bulky, bolt-on solar 

PV systems that have dominated the 

market in the past. 

Single source supply 

Using what can be unfamiliar technology 

such as solar PV means that teaming 

up with a single manufacturer, such as 

Marley, can be operationally sensible and 

cost efficient. 

Already a supplier of full roofing 

systems, the ability to access Marley’s 

high performing solar PV solution, 

Marley SolarTile, as part of overall 

roofing designs can help ensure a 

trouble free and seamless planning 

and installation process. Construction 

timescales can be maintained with 

delivery to site assured, whilst the 

back up of a 15-year guarantee that 

comes with Marley’s full roof system, 

means peace of mind for construction 

companies and their clients. 

Those involved in the construction of 

green buildings, both on a commercial 

and residential scale, can differentiate 

themselves by providing sustainable 

product solutions such as integrated 

solar PV, battery storage, heat pumps, 

and EV charging points – all of which 

will aid reduced cost energy generation 

and deliver low carbon heat. 

This will not only help the sector 

to meet its short and long-term 

obligations under Part L and the 

Future Homes Standard, but those 

who place sustainability at the heart 

of their construction offer will delight 

discerning would-be buyers who are 

increasingly prioritising greener and 

lower cost energy solutions for their 

homes. 

Contact Marley 

www.marley.co.uk/solar 

Tweet: @MarleyLtd 


Specify insulation 

that stands the 

test of time… 

Creating tomorrow’s green 

roofs, today. 

Save time and future costs by specifying ROCKWOOL stone 

wool insulation, which has shown to retain its insulation 

characteristics and properties for more than 55 years after 

initial installation. 

Stone wool insulation delivers key benefits for green roofs: 

Durability 

Stone wool insulation is dimensionally stable and its 

performance won’t deteriorate over a building’s lifetime. 

Fire safety 

Stone wool insulation can withstand temperatures 

in excess of 1,000ºC and will not burn, helping to 

mitigate the possible fire risks of dried-out vegetation. 

Thermal properties 

Stone wool offers exceptional thermal performance, 

contributing to energy efficiency targets and enhancing 

indoor comfort. 

Acoustic performance 

Trapping sound waves, ROCKWOOL stone wool 

insulation helps to dampen excess noise. 

For a total insulation solution which guards against deterioration 

and futureproofs for tightening fire safety and energy efficiency 

requirements, choose ROCKWOOL stone wool. 

To learn more, 

visit the new 

ROCKWOOL 

Flat Roof Resource 

Hub today: 

rockwool.com/uk/ 

flat-roof-hub/ 

www.rockwool.com/uk


AESTHETIC APPEAL AND ENERGY 

PERFORMANCE FROM YOUR ROOF SYSTEM 

The Crest Nelskamp Planum and G10 S PV integrated solar pv system is a quick and easy to fit 

system that works seamlessly with Crest’s Planum concrete and G10 clay roof tiles, offering a 

state-of-the-art solution for the completed roof. 

With an increasing focus on 

sustainable solutions in the built 

environment as the UK looks 

to reduce its greenhouse gas emissions, 

Crest Building Products offers the Crest 

Planum and G10 Clay PV Integrated solar 

system. They are engineered to fit quickly 

and are installed at the same time as 

the roof, interlocking easily with Crest’s 

Planum concrete flat tiles and the G10 clay 

tiles. Crest’s PV Solar Tile solution provides 

an almost seamless, attractive finish to 

the completed roof, whilst supplying the 

homeowner or building owner with an 

instant clean and efficient energy supply. 

A key benefit for installers is that the 

simple and quick interlocking ‘plug and 

play’ installation method makes the solar 

roof tile ideal for both new build and 

renovation projects. This makes it an 

ideal and accessible option for roofing 

contractors who are looking to expand 

their offering and capitalise on the 

demand for energy efficient products. 

The Planum and G10 solar roof tiles are 

made from quality materials which have 

been specifically selected and tested to 

ensure optimal solar return with highly 

efficient monocrystalline solar cells. 

Both modules come with a product 

guarantee of 10 years, whilst users will 

enjoy a performance guarantee of 90% 

of rated performance for 10 years, and 

80% for 25 years, ensuring they can 

make the most of their installation. 

*Planum Concrete PV - buildingintegrated 

photovoltaics 

The Planum PV module fits with the 

Planum and Planum Duo concrete roof 

tile and has a deck width of 1500mm (5 

roof tiles) as well as a variable deck length 

between 32.5 - 34.0cm. The module has 

hanging lugs which are attached to the 

roof battens and fixed with a screw, and 

the solar panels interlock with the Planum 

roof tile. With only approx. 5.5m roof area 

per kWp output, it is extremely powerful 

and impresses with the clear lines on the 

roof. 

Above: The G10 integrated module offers 

complete synergy between the roof and the 

solar panel. 

G10 S PV - building-integrated 

photovoltaics 

The G10 S PV module fits with the flat, 

smooth clay roof tile G10 and has a cover 

width of 1494mm (6 roof tiles) and a 

variable cover length between 38.4 - 

40.4cm. The module has hanging lugs 

with which it is hung on the roof battens 

and screwed as well as a fold on both 

lateral ends that correspond to the fold of 

the G10 tile. 

With only approx. 5.6m 2 roof area per 

kWp output, it is also one of the very 

powerful BIPV modules using the latest 

half-cut cell technology. The slightly 

higher cover length leads to a slightly 

higher frame proportion, which is used 

for an aesthetic notch at the base of the 

tile. This notch simulates the tile joint and 

thus underlines the roof tile aesthetics. 

Furthermore, the base of the tile is 

toothed in order to allow for additional air 

ventilation and cooling. 

Above: The Planum integrated solar panels have subtle attractive looks and are virtually invisible. 

Contact Crest 

Building Products 

www.crest-bst.co.uk 

Tel: 01430 432 667 

34 GREENSCAPE SPRING SUMMER 2022 • • www.greenscapemag.co.uk

GUARANTEE 

CREST NELSKAMP 

PLANUM CONCRETE AND G10 CLAY 

PV INTEGRATED SOLAR SYSTEMS 

A quick & easy to fit system that works seamlessly with the Crest *Planum concrete 

and G10 clay roof tiles offering a state of the art solution on the completed roof. 

The Integrated solar panel roof tiles are both a 

roof covering and electricity generating solution. 

> Beautiful aesthetics 

> No more ‘Ugly’ Solar Panels! 

> Engineered to fit quickly and easily 

> Modules interlock with Planum & G10 roof tiles 

> Easy to connect MC4, simply plug and play 

> Performance guarantee: 

10 years 90% of rated performance 

25 years 80% of rated performance 

‘ECO’ 

FRIENDLY 

PRODUCT 

QUICK 

AND EASY 

INSTALLATION 

WITH 2-3 

SCREWS. 

Crest *Planum PV Solar 

Tile Panel, with black 

frame - black cells and 

black backsheet 

*As per European trademark Nr.7287956, filed on 2nd October 2008, the Trademark 

PLANUM belongs to La Escandella. It is Dachziegelwerke Nelskamp as authorised 

licensee of the owner allowed to use the mark PLANUM for its concrete product. 

For more information on our roofing tiles and PV 

integrated solar system contact the Crest team. 

TECHNICAL 

S U P P O R T 

30 

Y E A R 

01430 432667 info@crest-bst.co.uk www.crest-bst.co.uk 

ROOFING TILES

Summer '22

Create successful ePaper yourself

Delete template?

Save as template?