The intent of this credit is to reduce the thermal gradient differences between developed and undeveloped land by implementing the use of highly-reflective or vegetative roofing surfaces.
Requirements for Certification:

Option 1 - Use roofing materials with an acceptable Solar Reflectance Index (SRI) for 75% of the roof surface. SRI must be equal to or greater than 78 for a low-sloped roof (less than 2:12 slope) or 29 for a steep-sloped roof.

Option 2 - Install a vegetated roof for at least 50% of the roof area.

Option 3 - Use a combination of the strategies above such that: (SRI Roof compliant area / 0.75) + (Vegetated Roof / 0.5) >= Total Roof Area.

Successful Strategies:

• Vegetated/Garden Roofs
• Energy Star rated roofing systems
• High reflectivity coatings

Helpful Hints:

1. Highly reflective and emissive roofs do not only mean white roofs. A wide variety of roofing colors and styles meet the minimum SRI requirements.
2. White membrane roofs are not as good in kitchen/restaurant applications as they quickly degrade under grease exhaust.
3. Confirm roofing cutsheets indicate surface reflectivity and emissivity to calculate the SRI through ASTM Standard E1980-01.
4. Garden roofs may be difficult to permit (due to stormwater run-off related issues) in jurisdictions where it has not been applied.

Historical Data (updated June 2006):

• 61% of all California LEED Certified projects achieved this credit for LEED v2.1.

Additional EDR Resources

Case Studies: Thinking outside the Box

Design Briefs: Design For Your Climate

E-News for Designers: e-News #24: Heat On A Cool White Roof: The Energy Efficiency Benefits of Reflective Roofing Materials.