California residents who wish to renovate their homes or add a room will encounter the phrase ‘Title 24’.

All energy regulations for both commercial and residential properties are bundled together in what’s called ‘Title 24’. It’s a relatively new requirement for a good cause, and ensures all business establishments and homes are energy efficient and have good indoor air quality to an acceptable degree.

Title 24 is part of a larger phrase. The whole title is ‘Title 24, part 6 of California Code of Regulations’. Stakeholders and the California Energy Commission, or CEC come together every three years and discusses tech advancements and how they could be implemented.

Title 24 began in the 70s and has enjoyed constant updates. The aim of the regulation is to reduce energy use and greenhouse gas emissions and improve both indoor and environmental air quality.

The main concern for homeowners is whether the renovation they intend to make is covered under Title 24.

Generally speaking, all new construction, including kitchen, living room and bathroom renovations are affected, as well as a garage extension and adding new rooms or living spaces.

To be Title 24 compliant means you will need to meet and pass the requirements as set by the regulation.

The whole of California is divided into climate zones under Title 24. Each zone will have a unique set of legal requirements, and understandably so. Local climate can and will determine the energy efficiency, which is then followed by architects and contractors.

Attics in particular are subject to a few paragraphs in Title 24. Roof and ceilings must have insulation or ventilation, and its R-Value should meet or exceed the zone’s requirements.

To the uninitiated, R-Value is an insulation’s heat flow characteristic, or how hard it is for heat to pass through. The higher the R-Value the better it is in insulating against heat and cold.

If you’re building a new house in California, you will have to meet the minimum R-Value the California Energy Commission has set. This applies to contractors as well. The entire state must abide by the R-30 specifications set, which may only be superseded by R-38 and depending on where the building is located by climate zone.

Ceiling and roofing constructions will have its own set of Title 24 requirements. Ceilings and roof constructions that make use of metal frames will need at most a .031 U-factor, and zero frame insulation penetration must have at least R-30 values and pass compliance tests. It’s only acceptable if the roof and ceiling has at least .031 U-factor or less.

If there’s any insulation to be added then it must have at least an R-30 value and meet performance methods. Prescriptive compliance minimum must be R-30 or R-38 depending on where the site is located in terms of climate zone. For roof alterations, the material to be used must have at least an R-Value 19 and meet compliance standards.

California code states that ceiling and roof insulation must be connected to the infiltration barrier. Contractors will often choose to install the infiltration barrier to the drywall, then suggest a vent in the attic. In this situation the insulation may be connected to the ceiling straight away.

Ceiling insulation must cover the bottom chords of the trusses and the outer wall. It must not block eave vents in the attic at any point due to potential air flow problems. Not enough air passing through will result in excessive moisture, and water vapor starts accumulating on the underside of the roof, thereby causing insulation and structural damage.

Contractors often recommend tapering the insulation at the eave. When this happens the insulation must cover the entire ceiling and still meet the minimum R-Value.

After inserting loose-fill insulation contractors must check to see if the R-Value is met or exceeded according to the site’s climate zone. Furthermore it must meet the minimum weight as manufacturer specifications.

Insulation must be applied evenly. Kraft and foil-based material must meet manufacturer specifications to minimize air leaks and prevent sagging. Insulation must meet and connect the rim joists within the plane.

Vapor barriers may be installed on the conditioned side of the frame. Inspecting wall insulation is understandably more difficult especially when it’s positioned in tub and shower areas but the contractor must still carry on to ensure it’s compliant with local code.

Contractors must check and see if the insulation is connected to the sub-flooring in order to avoid air pockets from forming. Support may be added to prevent falling, sagging or deterioration. Hangers can act as support when it comes to netting, joists and others. In this situation the contractor must have an allowance of 18 inches between hangers before the insulation is installed.


Insulation hangers may be used to attach insulation to the wood. Netting and mesh may be applied to the underside of the joists, and foundation vents must not have any obstruction coming from insulation.

Title 24 is a collection of construction rules that benefits all concerned. Following it means the residential or commercial property has all the elements that make up an energy-efficient property. With good insulation and sound recommendations property owners can look forward to a more comfortable living space and lower energy consumption.

At Attic Insulation Expert we take the time to understand what Title 24 is all about and how it can help residential and commercial property owners. Our licensed contractors are fully aware of Title 24 and its stipulations for attic, ceiling and floor insulation.

Improve Home Comfort with Attic Insulation Expert

Attention to detail and achieving full compliance is standard in our books. Attic Insulation Expert uses the latest insulation material to bring energy efficiency in homes and businesses and meet Title 24 rules at the same time. Orange County, Ventura and Los Angeles customers can get peace of mind knowing their attic, ceiling and floor insulation meet or exceed R-Value as determined by their local climate zone. 

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