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  • Lorianna Kastrop

New Title 24 Energy Standards

On July 1, 2014 new Title 24 standards will go into effect. California’s Title 24 is the part of the state building code that defines energy efficiency requirements for both residential and nonresidential buildings. The new standards will replace the 2008 version and there are some major revisions that will go into effect. You can get a full copy of the 2013 Building Energy Efficiency Standards (263 pages, pdf format), plus a lot of other relevant information at this website:

A more user-friendly summary of the changes to the Lighting Requirements is available here:

The energy savings due to the new Title 24 standards are expected to be significant. According to the CA Energy Commission Publication 400-2013-009, the differential from the 2008 code will result in annual savings of 11 million therms of natural gas and 447 gigawatt-hours of electricity. The goal is to provide lower energy costs, improved comfort and environmental benefits.

Here is a sample of the significant changes. (This is not a complete list.) Unless otherwise noted, these changes apply to both residential and nonresidential construction.

  1. For standard wood-framed buildings, wall insulation will increase to R15+4 in all climate zones. (Section 150.1(c)1B). This requires use of 2×4 studs, 16” on center, with R-15 insulation plus R-4 rigid insulation on outside of framing, or 2×8, 16” on center with R19 insulation.

  2. On new construction of single family residences, at least 250 square feet of roof must be a “solar ready zone”) suitable for installation of solar photovoltaic panels. (Section 150.0(r)) Other “cool roof” requirements may also apply. (Section 140.3(a)1Aia1)

  3. On commercial buildings the amount of glazing is now restricted. The window to wall ratio is 40%. This will have a major impact on the look of high-rise buildings.

  4. Window (fenestration) requirements have been changed to a U-factor of 0.36 for fixed windows and 0.32 for operable windows. Right now there are only a couple of manufacturers offering window products that comply with the new requirements. The industry is expected to quickly produce more compliant products in the near future, but windows that are specified for projects submitted for permit in late 2014 will have to be specified carefully. (Section 140.3(a)5B,C&D)

  5. Heating, ventilation and air conditioning (HVAC) requirements will be much more stringent. For example, all ducts must be sealed and pressure tested. (Section 150.0(m)11)

  6. In commercial buildings there must be individual controls in all areas to automatically shut off or reduce lighting and other plug loads when the area is not occupied. This means that there will be motion detector or other sensors in each area. Also, equipment that must remain running without powering down or without a “sleep” mode will have to be on an outlet specially designed and identified for that purpose. This requirement applies to all of the following: private offices, open office areas, reception lobbies, conference rooms, kitchens, copy rooms, classrooms, indoor parking garages, warehouse & library aisles, corridors & stairwells, etc. (Section 130.1 and Section 130.5) Occupancy controls will also apply to Hotel/Motel guest rooms (Section 120.2(e)4 & Section 130.1(c)8).

  7. Triggers have changed. For non-residential buildings, the code only allows 10% or less of the lighting fixtures to be replaced before the change triggers full compliance with the new requirements. For example, if a building owner chooses to replace fluorescent fixtures with high-efficiency LED lighting in more than 10% of the building, then all of the lighting must become compliant with the new requirements. Details on triggers and other compliance information is available at

As you can see from this relatively brief overview, the 2013 Title 24 standards will have a major impact on design and construction, as well as on costs. If you have a project in the near future, check to insure that your architect is working with the new building code and has taken the revisions into consideration.

For any projects currently in the design process, we highly recommend that you contact your architect immediately to see if you can submit your plans before July 1st, so that you will not be impacted by Title 24 changes to the design.

Lorianna Kastrop Vice President The Kastrop Group, Inc. Architects

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