Lighting Design + Application • October 2003 - Illuminating ...

New Existing No. ofBuildings Buildings Points20% 10% 230% 20% 440% 30% 650% 40% 860% 50% 10Table 1—Credit 1 optimize energyperformance 2-10 pointsway, parking and ball field lighting levelsare not specified in this document,but are referenced to other documentswhich adds to the confusion.A change from 2.0 for this credit isa requirement to use shielded luminairesfor fixtures with more than1000 lumens,and only full cut-off typeluminaires for fixtures with morethan 3500 lumens.The maximum candela value of allinterior fixtures must remain in thebuilding. For exterior fixtures, themaximum candela value must remainwithin the property line. If a fixture iswithin 2.5 times its mounting heightfrom the property line, it cannot contributeany direct beam illuminationoff-site. An illumination calculationshowing the illumination of the site isrequired for submission.At first glance this concept seemsstraightforward, but in the context ofa real project, it can become lessclear. For example, in an urban environment,buildings are typically builtat the property line. Any lightattached to the building facade or toa canopy is lighting someone else’sproperty. To complicate things further,in Seattle, for example, the buildingcode requires illumination ofareas under canopies to at least fivefootcandles.This would seem to be adirect conflict with the requirementto not light beyond the property line.To find out how to deal with issueslike this, two free credit interpretationsare available per project. Thedesign team submits its question inwriting to the LEED reviewer whowill make a ruling.Access to all previouscredit interpretations is availableafter project registration, so beforeusing one of your free questions, youcan check to see if someone else hasalready asked the same question. AllLEED accredited professionals haveaccess to the credit interpretations.Energy And AtmosphereCredits 1.1 1.5 Optimize Energy Performance(2-10 points)The focus of these credits is energyreduction.The greater the reduction,the more points available. Table1 shows how much the energy mustbe reduced to reach each level.Energy savings is based on total buildingenergy use (envelope, HVAC, servicewater heating, electrical powerdistribution, metering provisions,electric motors, belt drives and lighting).Since this category considersoverall building energy, it’s an areawhere coordination between disciplinesbecomes very important.One prerequisite of this categoryis that you must first meetASHRAE/IESNA 90.1-1999 or thelocal energy code, whichever is morestringent. The energy savings toachieve the point are based on savingsas compared to ASHRAE/IESNA90.1-1999. This puts projects acrossthe country on the same measuringplane. If the project is located in anarea where the local energy codesare more stringent than ASHRAE,you could get a few “free” points withthis credit. Documentation of thiscredit is generally the responsibility ofthe mechanical engineer, with inputfrom the electrical engineer and thelighting designer. Fundamental buildingcommissioning is also a prerequisitefor this category.To certify a building under LEED,the project must first be registeredwith the USGBC. The earlier this isdone in the design process, the better.Usually the architect or a LEEDconsultant takes on this responsibilitybut it could also be done by theowner or the contractor in a designbuildscenario.The actual documentationis submitted after construction iscomplete but should be collectedduring the project when it is mosteasily available.Clearly there is much value in followingLEED guidelines.As designers,we can make a valuable contributionto the design team by being familiarwith the process and knowledgeableabout the points related to our discipline.Denise Fong, IALD, FC, is principal ofCandela Architectural Lighting Consultants,Seattle,WA.