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What is Title 24, Part 6? The Nation's First Solar Mandate in California

Publish Date: February 25th, 2019

As a Colorado solar company, Namaste Solar focuses our installation work along Colorado’s Front Range communities, but our residential design team completes designs and permit packages for home builders and construction professionals across the country. If you’re looking for help navigating the requirements of Title 24, Part 6 and the California solar mandate, contact our experienced design team.

 It’s not every day that building codes make national news, but last year the California Energy Commission (CEC) made headlines with a solar mandate under the revised Title 24, Part 6. The new building energy efficiency standards make California the first state to require solar for newly built homes.

The new Title 24, Part 6 standards officially take effect on January 1, 2020, but home builders, solar companies, and other stakeholders are already working to prepare for this big change. There is a lot to decipher in the updates, so we’ve put together the basics you need to know to understand the California solar mandate and updates to Title 24.

What is Title 24, Part 6?

The California Building Standards Code is outlined under Title 24 of the California Code of Regulations. Title 24, Part 6 outlines energy code for the state while other portions include building code, electrical code, fire code, green building code, and more. These standards are set by the California Energy Commission (CEC), the agency responsible for state energy policy and planning, and are updated roughly every three years. The 2019 standards go into effect on January 1, 2020 for building permit applications submitted on or after that date.

What’s Changing for 2020?

The updates made to Title 24 are designed to increase energy efficiency, save consumers money, and improve air quality both indoors and outdoors. The updated standards include a requirement for home builders to install solar photovoltaic systems on all new homes, making California the first state in the nation to have a solar mandate. New efficiency standards outline stricter requirements for insulation in attics, walls, and windows to save additional energy. Finally, the standards encourage measures such as battery storage and heat pump water heaters to shift energy usage to off-peak hours.

The California Solar Mandate

The new solar mandate in California will require all new homes to install solar PV systems. The solar mandate requirements are based on the floor area of the home and the climate zone, and the solar panel systems must be sized to provide for the full annual energy usage of the home. Even though the size of a home solar installation in California currently averages at 6.8 kilowatts, it’s expected that sizes will generally range between 2.7 kilowatts and 5.7 kilowatts under the new Title 24 requirements; that is because new homes will be more energy efficient overall.

Costs and Benefits of Title 24, Part 6

When drafting the updates, the CEC was required to show an overall cost savings for homeowners over the course of a 30-year mortgage. An outside consulting firm, Energy and Environmental Economics (E3), provided the analysis of Title 24 and showed that California’s solar mandate does result in net savings for homeowners. E3’s analysis shows that the new Title 24 requirements will increase the cost of constructing a new home by approximately $9,500 but will save homeowners $19,000 over the course of a 30-year mortgage. In other words, that’s an additional $40 cost per month for an average home but savings of $80 each month on heating and electricity.

Part of the goal for the Title 24 updates is to improve indoor and outdoor air quality while benefiting the environment. Across California, E3 projects that a total of 74,154 single-family homes will be built under the new code just in 2020, and the first year’s energy savings would result in 114,019 tons of avoided CO2 emissions. It would take 45,607 acres of forest land or 5.7 million trees to remove that amount of CO2 from the atmosphere in one year. And that’s just the first year! The homes built in 2020 will continue to save emissions for years to come, and more energy efficient solar homes will be built every year.

Home Builder Resources for Title 24

Our design team completed over 13,000 permit packages last year alone and has experience navigating requirements for hundreds of jurisdictions. We offer installation-ready solar PV permit packages for new home construction projects or consulting based on your needs, and we ensure fast turnaround times to help you meet your deadlines. Read more about Title 24 compliance and calculations or find out how Namaste Solar’s experienced residential and design team can help you navigate the California solar mandate.

Additional Resources