Many are at least somewhat familiar with green design programs such as LEED® and Green Globes. The ENERGY STAR® Roof Products Program and the Cool Roof Ratings Council have been providing lists of qualified or rated products for years now, however, recently there have been some questions about another design guide and what it has to say about cool roofing.
The Advanced Energy Design Guides were developed by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). The guides are a series of publications designed to provide recommendations for achieving energy savings above and beyond the minimum code requirements of ANSI/ASHRAE/IESNA Standard 90.1-1999. They are intended for contractors and designers of small buildings and provide a simple approach to achieve energy savings without utilizing complex calculations or analysis.
The guides give general recommendations in the Building Envelope sections stating that cool or “solar reflective” roofs help reduce energy usage. They do not offer the specificity of LEED or Green Globes, rather they make general recommendations like “increase roof surface reflectance and emittance.”
They also provide useful charts and climate maps that indicate relative performance of various types of roofing products and areas of the country that may benefit most from cool roofing systems.
The Advanced Energy Design Guides are available as free downloads from www.ashrae.org/aedg. Highly reflective white membranes, such as what’s used in the Duro-Last® Cool Zone® roofing system offer a great opportunity for owners of small buildings to achieve real energy savings.