You’ve probably heard of LEED, (Leadership in Energy and Environmental Design), and maybe if you’re in California you have heard of GreenPoint Rated or the eminent CALGreen Code, but wrapping your head around how these standards compare and what they mean to your building project can be a big task. In this article, I’ll try to break it down a bit. For more detailed information, please visit the web sites of each compliance organization: LEED, GreenPoint or CALGreen
LEED, developed by a non-profit organization called the U.S. Green Building Council, was really the forerunner in developing an industry standard for sustainable building practices in the United States. GreenPoint Rated (GPR) is a system used for houses and developed by Build It Green, another non-profit based in California, with the goal of creating a standard that would be less expensive and therefore more accessible to homeowners. CALGreen is a building code that will become effective in California for both residential and commercial buildings on January 1st, 2011. Some municipalities in the Bay Area are even requiring permit applicants to get certification from GPR and/or LEED as a way of ensuring that CALGreen standards have been met.
Both GPR and CALGreen systems of measurement are based loosely on the LEED standards, but there are some differences and modifications made to clarify or make easier the systems of measurement that are in place. For simplicity, I’ll compare the residential measures as a common base for all three systems. All systems break green building components down into areas of sustainability that they are addressing with varying names and sub- categories. However, the general concept is shared: sustainable building practices fall into these categories:
- Planning/Site/Community
- Water Efficiency
- Energy Efficiency
- Material Resources
- Environmental /Air Quality
GPR arranges their checklist in a way that relates more closely with building systems themselves such as structural frame and finishes, but are then cross-referenced with one of the above categories. All of the systems have mandatory or prerequisite measures that must be met, and the two voluntary systems (LEED and GPR) have additional strategies that go above and beyond to earn points. A minimum number of points is required for certification, and the more points earned the higher the level of certification.
Since LEED and other green building certification systems have begun gaining popularity, there have been a number of articles and independent studies published on the value added by achieving certification, such as “An Inconvenient Value” by www.AwarenessIntoAction.com and “The cost & benefit of achieving Green buildings” by Davis Langdon. We hope the trend continues to catch on and the up-front cost continues to come down as demand for sustainable building materials and methods continue to rise.
Now let’s dig a little deeper into the subcategories and the particular goals of each. The charts below are not meant to be comprehensive, but instead give an overview, hitting the highlights of each system. Note that The CALGreen system has two “Tiers” that can be sought, which require additional prerequisites. I’ve included these prerequisites under ‘additional points/measures’ in order to maintain clarity of the basic requirements in the charts below.
Bridgett Shank works at Feldman Architecture and is a frequent contributor to Green Architecture Notes.