Residential buildings: indoor temperature.

Senator Stern's residential temperature control legislation would establish California's first maximum indoor air temperature standard of 82 degrees Fahrenheit for newly constructed homes, addressing rising concerns about extreme heat exposure. The Department of Housing and Community Development must research and propose implementation standards for the 2026 California Building Standards Code update, potentially incorporating mechanical ventilation, natural ventilation, shading and other cooling techniques.

The bill directs the California Energy Commission to create an inventory of incentive programs supporting alternative cooling strategies, including cool roofs, window shading, weatherization and strategic landscaping. For residents in high-heat climate zones, the Public Utilities Commission would modify baseline utility rate calculations with the goal of keeping average electricity bills below 5% of household income while maintaining the 82-degree indoor temperature target.

The legislation responds to data from the State Department of Public Health documenting 395 excess deaths during a 10-day heat wave in September 2022. Current building codes mandate minimum indoor temperatures of 68 degrees but contain no maximum temperature requirements. Both the Building Standards Commission and Housing Department must submit implementation reports to the Legislature, with reporting requirements sunsetting in 2031.