Welcome to the California Energy Commission

2005 Standards Information

Cool Roofs and Title 24

Cool roofs are highly reflective, highly emissive roofing materials that stay 50 to 60 degrees F cooler than a normal roof under a hot summer sun.

Cool roofs can cut building owners' energy costs. Because cool roofs gain less heat than normal roofs, they reduce the need for air conditioning making buildings more comfortable to the people inside.

Cool roofs have other benefits, too. For building owners they can cut maintenance costs and increase the life expectancy of the roof. And for society in general, cool roofs can even help to reduce the urban heat island effect that makes our cities hotter and produces unhealthy air.

Because cool roofs save both money and energy, in October 2005 they became part of the prescriptive requirements of California's energy code, the Title 24 Building Energy Efficiency Standards. Most cool roof materials for low-sloped roofs are white or another light color. Because steep-sloped roofs are often visible from the ground, however, roofing material manufacturers have developed popular roof colors other than white that will still reflect or emit the sun's energy away from the building.

Cool Roof Resources

Roofing Contractor Training (Acrobat file, 1 mb)
Cool Roof Training Videos
Cool Roof Regulations Excerpts - 2005 Building Energy Efficiency Standards (Acrobat file, 152 kb)
Blueprint # 83, Q&A on Cool Roofs (Acrobat file, 1.4 mb)
Blueprint # 86, Cool Roof Update (Acrobat file, 1.7 mb)
Questions and Answers for Building Owners - 2005 Building Energy Efficiency Standards (Acrobat file, 128 kb)

Commercial Reroofing

Steps to Help Decide if a Cool Roof is Right for You (Acrobat file)

Sample Forms to Meet Building Criteria
Sample Form - Commercial Reroofs (Generic Sample Form)
Sample Form - Commercial Reroofs (City of Vacaville)

Cool Roof Rating Council

The Cool Roof Rating Council is an independent organization that lists the solar reflectance and thermal emittance specifications for many roofing products. CRRC is a valuable resource for building officials; energy service providers; architects and specifiers; property owners and community planners - anyone seeking to improve the energy efficiency of their buildings.

www.coolroofs.org - CRRC website

Web-based R-value Calculator for Reroofs

A calculator is now available to quickly determine the energy-equivalent R-value of insulation needed to meet title 24 requirements if a building owner chooses to install a non-cool roof during a reproofing project.

Developed by the Asphalt Roofing Manufacturers Association (ARMA) in conjunction with Oak Ridge National Laboratory, and the Energy Commission, the calculator takes into account the level of existing insulation, the climate zone, and several other factors that determine the proper R-value of required insulation.


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