Green Roofs - Living Architecture Monitor - Fall 2011 - (Page 20)
POLICY
CODE BREAKTHROUGH
GEORGIA ENERGY CODE AMENDMENT NOW RECOGNIZES GREEN ROOFS
By Bourke Reeve and Mike Barcik
T
here has been a major push over the past year for states to adopt and enforce the 2009 International Energy Conservation Code (IECC) and 2007 American Society of Heating Refrigeration and Air Conditioning Engineers (ASHRAE) Standard 90.1. The force behind this momentum is the American Reinvestment and Recovery Act (ARRA). All 50 states accepted ARRA funding from the federal government and as part of that funding agreement these states committed to adopt and
enforce the 2009 IECC. States adopting the code may choose to make amendments to the code as long as the code is not weakened by these amendments. The IECC is an energy code that sets minimum standards for energy efficiency in residential and commercial buildings. IECC Chapter 4 covers residential structures up to three storeys while Chapter 5 covers commercial buildings and residential structures four storeys and above. Within Chapter 5 of the 2009 IECC, Standard 90.1 – 2007 is referenced as an alternative compliance pathway for commercial structures. While the two codes are very similar, some differences exist. One of these differences is a “cool roof” credit incorporated into ASHRAE 90.1 – 2007. Architects and engineers working on design projects may choose the compliance path (ASHRAE 90.1 or IECC Chapter 5) that works best for their project. In Georgia, the ASHRAE 90.1 – 2007 code was amended to extend the “cool roof” credit to include green (vegetated) roofs as well. This amendment to the code allows designers to incorporate a green roof into the design of a commercial building in Georgia and take credit for the cooling effect of that roof. The cool-roof credit can then be traded against insulation requirements in the roof or traded to another part of the envelope. This credit allows for cost-shifting between the green roof and the insulation in the building. When the multiple benefits of green roofs such as stormwater management, reduction in urban heat island, promotion of biodiversity and the addition of a building amenity are factored in, the importance of this simple amendment is clear. Incorporation of green roofs has many benefits and now those benefits are recognized in the Georgia Commercial Energy Code. Other
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LIVING ARCHITECTURE MONITOR
FALL 2011
http://www.greenroofs.orghttp://www.greenroofs.orghttp://www.gpgb.org
Table of Contents for the Digital Edition of Green Roofs - Living Architecture Monitor - Fall 2011