01Title 24 is a whole code; Part 6 is the energy piece
Title 24 of the California Code of Regulations is the state’s building standards code. It is divided into parts covering structural, electrical, plumbing, fire, green building and more. Part 6 contains the Building Energy Efficiency Standards, usually called the Energy Code. When a plan reviewer, designer or contractor mentions a “Title 24 report,” they almost always mean documentation showing compliance with Part 6.
Part 11, known as CALGreen, is a separate green building code. Some projects deal with both. They have different requirements and different documentation, so it helps to keep the names straight when asking questions.
02Who maintains it and how it changes
The California Energy Commission (CEC) develops and adopts the Energy Code. Updates happen in cycles, historically about every three years. Each cycle can change requirements for envelope, mechanical systems, water heating, lighting, solar and other topics. Local building departments enforce the code, and some jurisdictions adopt local amendments, often called reach codes, that go further.
Because the applicable cycle and any local amendments depend on when and where a permit application is made, it is worth confirming both with the reviewing building department before documentation is prepared.
03Three layers of requirements
Most projects encounter three kinds of requirements:
- +Mandatory measures, which apply regardless of the compliance approach chosen
- +Prescriptive requirements, a component-by-component path with listed values
- +The performance approach, which uses CEC-approved software to compare the proposed design against a standard design and allows trade-offs
04Why it matters early in design
Energy decisions influence window sizes and products, wall and roof assemblies, duct and equipment locations, water heating and sometimes roof layout for solar. Discovering a compliance problem at plan check usually means redesign, resubmittal and delay. Considering energy during schematic design or design development is generally cheaper and smoother.
This article is general orientation, not engineering or legal advice. The CEC website is the primary source for the current standards, compliance manuals and approved software.
05Common misunderstandings
A frequent misunderstanding is that the Energy Code only matters for new homes. In practice, additions, many alterations, equipment replacements and commercial tenant improvements can all involve Part 6 requirements. Another is that energy documentation is a formality completed after design; because the documents describe specific products and assemblies, they work best when prepared alongside the drawings. Finally, compliance documentation is not a forecast of utility bills. It uses standardized assumptions to determine code compliance, and actual energy use depends on occupants, weather, maintenance and many other factors.