California Title 24 & Radiant Barriers

All RadiantGUARD® radiant barrier and bubble insulation products have been licensed with the State of California for Title 24 compliance.

Please contact us for our State of California Department of Consumer Affairs license number for Title 24 radiant barrier qualification credit.

What is California Title 24

Energy efficiency reduced energy costs, increases reliability and availability of electricity, and reduces impacts to the environment.  Therefore, energy efficiency standards are important and necessary for California's energy future.

The 2005 Residential and Non-Residential Standards are expected to reduce the electricity usage growth by 478 gigawatt-hours per year and reduce gas usage growth by 8.8 million therms per year.

When Are Radiant Barriers REQUIRED Under Title 24 Standards?

There are two approaches to complying with the 2005 Residential and Non-Residential Standards.  Using the prescriptive approach, each building component must meet a prescribed minimum energy requirements and the total package must meet all of the requirements for the climate region. 

Using the performance method, the builder uses an approved computer model to calculate the energy budget for the building.

Radiant barriers are required for the following climate zones with significant cooling loads when using the prescriptive approach:

  • Zone 2,

  • Zone 4, and

  • Zones 8 through 15

Allowed Methods of Installation for Radiant Barriers

The California Energy Code mandates radiant barriers be installed in one of the following methods:

  • Stapled to the underside of the roof decking,

  • Draped over the truss cords or rafters,

  • Stapled to the inside of roof rafters, or

  • Stapled to the bottom of the truss cords or rafters.

There must be a 1 1/2 inch air space below the roof deck and an air space of 3 1/2 inches from the insulation on the roof decking to allow ventilation air to flow between the roof decking and top surface of the radiant barrier.  A minimum of 6 inches (measured horizontally) should be left at the roof peak to allow hot air to escape from the air space between the roof decking and the top surface of the radiant barrier.

Radiant barriers must be installed on gable ends as well.

See our radiant barrier installation techniques for installation guidance.