A Guide to California’s Title 24: Renovating and Energy Efficiency

What you need to know when remodeling in the energy-efficient state

Los Angeles(Above) Los Angeles renovation by Sweeten contractors Anna and Vahik

Any homeowner who plans on renovating their home or adding an addition to it will soon become familiar with Title 24—energy regulations for all residential (and commercial) buildings in California. Officially called “Title 24 Part 6 of the California Code of Regulations,” Title 24 was put in place in the late 1970s and has been updated periodically since then. Currently, the regulations are updated every three years. The changes from the periodic updates allow the regulations to keep pace with new technologies and help the state reach its stated goals of reducing energy use, reducing greenhouse gas emissions, and ensuring both indoor and outdoor air quality.

The process is working. Studies conducted in 2015 showed that energy consumption per household in California was 31 percent less than the national average. Energy bills were 21 percent less than the national average.

What should Californians know before they start demolition? Sweeten, a free service matching renovators with vetted general contractors, offers this basic guide to the paperwork and professionals needed for code compliance.

What is covered by Title 24

All new construction is covered. For homeowners who want to add living space to an existing home or renovate an existing space,  the regulations apply to a number of projects. All additions must conform to the regulations, including projects like converting a garage or enclosed porch into living space. The code refers to renovation projects as alterations and makes a distinction between alterations and repairs.

  • Alterations include any project that affects the envelope of the building, such as adding insulation or installing new windows; they also include changes to the water heating system, changes to the heating and cooling system, and changes to the lighting system.
  • Repairs refer to routine maintenance or fixing something that is broken. For example, if the central air-conditioning system fails to work and then is fixed, that is a repair. However, if the entire air conditioner or a major component of the air conditioner is replaced, the project falls under the regulations of Title 24.

It is an important difference because the energy requirements are among the most stringent in the country and the compliance process is difficult and sometimes confusing. In many cases, architects, contractors, or homeowners call in consultants to help them navigate the process—more on that later.

Complying with Title 24

The California Energy Commission has divided the state into 16 climate zones, each with its own requirements. Compare that to the seven zones the U.S. Department of Energy uses for the entire country. Energy standards do not vary that much from zone to zone—projects in some zones require R-6 duct insulation, while others require an R-8, for example—but the climate zones allow architects, contractors, and homeowners to develop the energy-efficiency package that is best for their local climate. For example, the city of Los Angeles contains two zones, while Los Angeles County contains five zones.

There are two ways to meet the requirements of Title 24:

  • The prescriptive method lays out a set of minimum standards that the project must meet. Requirements include insulation levels, the efficiency of water heating, and heating and air conditioning equipment, among others. It’s the easier of the two ways to comply with Title 24, but it does limit design flexibility. For example, the standards limit the amount of window area for additions over 700 square feet to 20 percent of floor area.
  • The performance method offers more flexibility. Basically, it allows tradeoffs in the energy design as long as the final project meets the requirement of the performance approach. For example,  the designer may add more window area as long as they beef up the insulation levels or install more efficient heating and cooling equipment. The overall design is analyzed by software that has been approved by the California Energy Commission.

To prove that the project meets the energy standards, whoever is responsible for the project, be it the architect, contractor or homeowner must supply a document trail for the local building authorities. An addition or large renovation will require a number of documents:

  • A Certificate of Compliance verifies that project plans meet the energy requirement of Title 24. While anyone can file the documents, many times an outside consultant is called in to advise on the project. The consultant, who is a certified energy expert, can prepare the necessary documents and submit them to the local building department which will issue the building permit. The consultant can also offer advice on the energy performance of the proposed project. Another option is to send the plans to a certified company to examine them for compliance. The results will be sent to the building department. The California Association of Building Energy Consultants has a certification program.
  • A Certificate of Installation is provided by contractors who install insulation, heating and cooling equipment, new duct work, water heaters, windows and lighting, and lighting controls. It provides a record that certifies proper installation techniques.
  • HERS (Home Energy Rating System) Verification takes place in the field. A certified HERS rater will inspect installations and do diagnostic testing to ensure compliance. For example, additions larger than 1,000 square feet require a mechanical ventilation system that must be tested and approved by the HERS rater.

These compliance documents are supplied to the local building department. The documents trigger the building permit, verifying that installation is done correctly and that the results meet the requirements.

2019 Standards

The next update is the 2019 Title 24, and it goes into effect on January 1, 2020. It includes increases in some energy requirements, but it also calls for solar photovoltaic—a technology that converts sunlight into electricity—to be part of all new residential buildings. The first such program in the country, the goal is zero net energy use for all new buildings.

Hopefully, this overview offers a clearer understanding of how to integrate California’s energy-efficient goals with the look and feel of the home you’ve always wanted.

Sweeten handpicks the best general contractors to match each project’s location, budget, scope, and style. Follow the blog, Sweeten Stories, for renovation ideas and inspiration and when you’re ready to renovate, start your renovation on Sweeten.

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