The State of California adopts model building codes for new and existing buildings every three years. Cities and counties can go beyond the requirements and enact stricter building codes if they want to promote green building, address seismic safety, or increase wildfire resilience, based on local conditions. In fact, California’s Title 24 contains a specific energy code section, “CalGreen,” that includes model “reach codes” that cities may voluntarily adopt to exceed minimum state requirements for building efficiency standards.
Pursuing Energy Efficiency with Energy Reach Codes
Since the beginning of August, Bay Area cities have passed a slew of energy reach codes focused on building decarbonization. ϴhelped develop these codes and get them passed. These efforts were hastened by the passage of Assembly Bill 130, , from October 1, 2025, to June 1, 2031, on the adoption of new state and local residential building standards and updates (for both single-family and multifamily residences) unless cities/counties to building electrification, greenhouse gas (GHG) emissions reductions, or other sustainability-focused language in their general plan.
Reach codes have significant potential for reducing building emissions and supporting cities to meet their climate goals. A number of Bay Area cities have advanced one or more of the following model building energy codes developed by the California Energy Commission:
AC-to-heat pump (AC2HP) codes require the replacement of conventional central air conditioners with ducted heat pumps when an existing unit burns out or when purchasing a new system. These codes save residents money on heat pump upgrades during economically beneficial timeframes while minimizing disruption. Compared with air conditioners, electric heat pumps are more energy-efficient because they can both heat and cool spaces. Unlike gas-powered appliances, they emit no particulate matter or nitrogen oxides, which cause smog — local air pollution that worsens asthma and other health conditions. Finally, they pose no risk of fatal carbon monoxide poisoning and are safer during earthquakes, fires, and other natural disasters. If all AC unit sales were converted to heat pump sales, more than half of California’s homes would in just five years.
Electric readiness codes require building owners to take steps to prepare for full electrification when making additions or alterations to an existing building, setting them up for the lowest possible-cost compliance with Bay Area Air District regulations. These steps include adding wiring for electric vehicle charging and electric stoves and, when necessary, upgrading electrical panels. SPUR’s Solving the Panel Puzzle policy brief presents information on electrifying while avoiding the latter measure.
FlexPath codes require building owners and contractors to choose from a “menu” of energy efficiency, electrification, or electric readiness measures when altering or adding to an existing building. These codes can be tailored to each city and include measures such as installing solar panels, increasing insulation, or electrifying a building.
All-Electric codes require all-electric new construction or major renovations projects with no gas appliances or gas infrastructure, which has the maximum reductions in emissions.
As of October 6, six Bay Area cities, with a collective population of more than 1.6 million people, had passed local reach codes:
- San Francisco passed a code requiring buildings that are undergoing major renovations to be all-electric.
- Oakland passed FlexPath and Electric Readiness Reach codes.
- Menlo Park passed residential AC2HP, FlexPath, and electric readiness reach codes.
- Sunnyvale passed residential AC2HP and electric readiness reach codes.
- Mountain View passed AC2HP and electric readiness reach codes.
- Palo Alto passed FlexPath, Electric Readiness, and AC2HP codes.
The City of San Mateo is AC2HP, electric readiness, FlexPath, and other reach codes.
Many jurisdictions in the Bay Area could benefit from decarbonization reach codes, especially those with high greenhouse gas emissions from buildings and heavy AC use, such as San José. With the exemption under AB 130 for code changes that align with a city’s general plan, it’s not too late for more cities to join the effort to decarbonize the Bay Area.
Leveraging Building Codes for Natural Disaster and Hazard Resilience
Just as jurisdictions can adopt energy reach codes to increase energy efficiency, they can amend municipal building codes to ensure that their buildings are resilient in the face of earthquakes, floods, fires, and other natural disasters. They can integrate resilience requirements as well as performance-based standards for disaster safety that exceed the criteria of formally adopted state building codes. Many strategies have both mitigation and adaptation benefits: shifting away from gas infrastructure improves safety during earthquakes and natural disasters while also preventing future climate change, and building with low-carbon concrete or mass timber (wood products that are engineered for strength and fire-resilience) can reduce supply chain emissions while strengthening seismic safety. California’s wildfire building code, Chapter 7A, mandates fire-resistant siding, tempered glass, vegetation management, and ember- and flame-resistant vents for attics and crawlspaces. However, this code applies only to new construction in one of the particularly high-risk zones mapped out by state and local officials.
Given the recency of this code (it was implemented in 2008) and California’s relatively old building stock, it will take decades to harden enough homes and priority buildings, such as hospitals and schools, to realize community-scale resilience. Retrofitting homes for seismic, flood, and wildfire resistance during renovations and property transfers — for example, by requiring or incentivizing the use of non-combustible roofing, double-pane windows, ember-resistant vents, and reinforced concrete or steel — can speed the pace of change. But very few municipalities have passed ordinances requiring resilient retrofitting. Some exceptions include Los Angeles, Santa Monica, and West Hollywood, which have ordinances requiring to improve seismic safety.
Some Bay Area cities have recently amended building codes to reduce their hazard risk. In June, the City of Berkeley passed an ordinance for the early adoption and expansion of “Zone Zero,” the defensible space rule that requires the removal of all combustible materials within five feet of structures. At its , the City of Oakland also made a series of emergency technical amendments related to seismic safety and high fire risk severity zones. Notably, AB 130 exempts building standards related to home hardening for wildfire resilience or those proposed by fire protection districts. This means that local jurisdictions can continue their home hardening and fire resilience efforts after October 1, as long as the California Building Standards Commission approves the efforts. According to a recent from the commission, AB 130 exemptions from the freeze on new residential building standards and updates do not include defensible space or resilience efforts in response to other threats, such as flooding, sea level rise, earthquakes, and extreme heat.
Just as purchasing a heat pump or laying the groundwork for electrification brings upfront costs, so too does clearing vegetation or replacing a wood shingle roof. Several rebates and financial supports are available for building decarbonization at the state and local level. Similar incentives are also available for hazard resilience:
- The program offers grants, often up to $3,000, to California homeowners for seismic retrofits.
- The is funding six neighborhood-wide retrofits in especially fire-prone and economically distressed areas of the state.
- Many local jurisdictions, including the and the City and County of San Francisco, provide grants to homeowners to implement defensible space efforts and initiatives.
- If signed by Governor Newsom, (The Safe Homes Act) would provide $3 million in state funding for low-income homeowners in high- or extremely high-risk fire severity zones to harden their homes.
Many insurance carriers offer better coverage, lower rates, and even discounts for homes that meet fire-resistant standards such as those developed by the Insurance Institute for Business and Home Safety.
Leaving No Homeowners and Residents Behind
Replacing wood siding is less expensive than replacing an entire home that burns, and swapping a heat pump for traditional air conditioning at the time the unit burns out saves money on both energy bills and heating costs. Nevertheless, prioritizing future safety or reductions in greenhouse gas emissions over immediate costs and inconvenience is often difficult. Berkeley and the six cities focused on decarbonization reach codes continue to move forward at a time when local action is more crucial than ever. The state must work to ensure that no homeowners or residents are left behind in this progress. It must provide adequate financial support to make California’s buildings more sustainable and resilient in the face of climate change.
Find information on .
Access a list of grants, resources, and assistance for .