This bill changes how disputes over building codes get resolved in California. Currently, if someone disagrees with how a local agency is interpreting or applying building standards, both the person and the local agency have to agree to bring the issue to the state's Building Standards Commission. This bill removes that requirement, meaning a person can appeal on their own once they've exhausted local appeal options first. It also expands the reasons someone can appeal, including requesting approval to use alternative building materials, and lets anyone ask the commission for an official interpretation of what a building code provision means. The commission will now be required to work with relevant stakeholders when reviewing appeals and must post all its decisions online in a searchable format so people can find precedents and guidance more easily. Additionally, local agencies will now be required to post their own building code interpretations and local rules on their websites, clearly labeled and linked to related amendments, rather than just making them available upon request. These changes apply to all cities, including charter cities, since the state has determined building code consistency is a matter of statewide concern. The bill may create additional costs for local governments, which would be reimbursed by the state if required.

This bill strengthens homeowners' ability to build accessory dwelling units (ADUs) by closing a loophole in existing law. Currently, rules preventing homeowners' associations from blocking ADU construction only apply to lots actually zoned for single-family use—this bill broadens that protection to any lot zoned to allow single-family use, even if it's not exclusively zoned that way, ensuring more properties are covered under these anti-restriction protections. The bill also doubles the number of detached, newly built ADUs that local governments must automatically approve on single-family lots, from one to two, without requiring special permits or extensive review, as long as they meet existing size and setback standards. However, if a homeowner builds two detached ADUs under this streamlined process, they won't also be entitled to automatic approval for a junior accessory dwelling unit on the same property. Because this creates new approval requirements for local governments, it qualifies as a state-mandated program, but the bill specifies that the state will not reimburse local agencies for these costs.

This bill changes how California handles the redevelopment of former military bases, specifically targeting the Concord Naval Weapons Station site. Normally, local governments must go through detailed notice and disposal procedures before selling public land, but certain large or special properties are classified as 'exempt surplus land' and skip those steps. SB 328 updates this exemption to cover the Concord site, as long as the local agency overseeing the land guarantees that at least a quarter of the housing built there will be affordable to lower-income residents for decades. To speed up construction, the bill also simplifies environmental review under CEQA for projects that match the site's already-approved area plan, meaning developers won't have to redo full environmental studies if their plans fit within previously approved land uses and density limits. If someone legally challenges a project, the bill sets strict timelines—courts must aim to resolve such cases within 270 days—and requires the developer to cover extra court costs tied to the case. Because these rules are tailored to this specific redevelopment effort, the bill includes special legislative findings justifying the unique treatment for the City of Concord. It takes effect immediately as an urgency measure, allowing redevelopment planning to proceed without delay while maintaining affordable housing commitments and streamlined legal review processes.

This bill directs the state's housing department to create standardized formulas and tools by mid-2028 that cities and counties can use to determine the realistic number of housing units that can actually be built on sites in their housing element land inventories. Local governments would be allowed to rely on these state-approved formulas when analyzing whether their available land can meet regional housing needs, and using these approved tools would be shielded from most legal challenges. The bill also requires housing inventories to clearly state how many units are currently allowed on each site versus how many will be allowed after any rezoning needed to meet housing targets. Additionally, it defines 'in-kind services' as a way local governments can fulfill commitments to provide affordable housing assistance to lower-income households, giving clearer guidance on what qualifies as sufficient support beyond direct funding. Overall, the bill aims to create more consistency and reliability in how housing capacity is calculated statewide, reducing disputes over whether a city's housing plan realistically accounts for its fair share of needed housing.