Considering cool roofs: 7 common questions asked by homeowners

By Owens Corning.

Help homeowners understand cool roof technology in asphalt shingles this summer.

As summer gets underway and many parts of the U.S. prepare for soaring temperatures, roof technologies and materials can help support “cooler” residential environments. Below are seven questions homeowners often ask about cool roofs that use asphalt shingles, and answers courtesy of Owens Corning.

1 - What is a cool roof asphalt shingle? 

A cool roof asphalt shingle is a shingle specially designed to reflect UV rays and help reduce shingle temperature. As a result, these shingles work to help keep a home’s roof cool throughout the year. 

2 - What is the solar reflective index and how does it relate to cool roofs?

Cool roofs are often evaluated using their minimum solar reflective index (SRI). SRI is a calculated value that combines solar reflectance (or how well shingles bounce the sun’s rays back into the atmosphere) and thermal emittance (or the measurement of how well a roof surface can release previously absorbed heat)¹.

3 - How do asphalt cool shingles work?

Cool roof asphalt shingles often use light colors and/or special solar-reflecting granules to help reflect UV radiation and reduce the amount of heat absorbed by the roof.

4 - How much can a cool roof improve indoor comfort?

Though individual savings may vary due to a variety of factors (a home’s age, amount and type of insulation, etc.), cool shingles can help reflect heat and UV rays which can help lower cooling bills and provide more comfortable temperatures inside your home.

5 - How much can a cool roof influence energy usage?

Cool shingles can potentially reduce the amount of energy needed to cool a home – helping to reduce energy usage and CO₂ emissions generated by energy use.

6 - Are there areas where cool roof shingles are required?

Energy efficient codes such as California’s Title 24, Part 6 say that a steep slope roofing product must meet or exceed an SRI rating of 16 or higher. The Green Building Standards Code of Los Angeles County and Los Angeles City Cool Roofs Ordinance also require that cool shingles meet or exceed 20 SRI. To learn more about roofing requirements in California (or your own local area), check out state and local building codes.

7 - Do cool roofs require special maintenance?

Cool roof asphalt shingles function like traditional asphalt shingles. Contractors and homeowners should review and follow specific manufacturers’ instructions to ensure they are properly stored, installed and maintained.

Homeowners can explore the Owens Corning® COOL Roof Collection Shingles here. These shingles are specially designed with solar-reflecting granules that offer performance without sacrificing beauty, ensuring homeowners get the color they want and the performance they need. 

 ¹(Understanding the Solar Reflectance Index:  A Calculated Value.  2022, July 12.  CRRC. coolroofs.org/documents/CRRC-SRI-Document_2022-07-12.pdf)