New energy design rating (EDR) metrics – EDR1, Title 24 Compliance now require to meet EDR1, efficiency EDR2, and total EDR2 separately.
- Space heating equipment must be a heat pump only in certain climate zone.
- Water heating equipment must be an HPWH meeting certain criteria or a solar water heating system with an electric backup.
- a gas instantaneous water heater in a certain climate zone is allowed if the space air conditioning unit is a heat pump
- install a tankless electric water heater with point-of-use distribution is allowed in the new unit under 500 SF
- a whole-house fan is not required in a new dwelling unit with a conditioned floor area under 500 SF
- Duct leakage testing is required for any extension of the existing ducting system.
- Space heating for addition requires to be a heat pump or gas heating system.
- Overall assembly title 24 U- Factor has been changed In many California climate zones
- If wood-framed, may install insulation of R-38 or greater.
- Whole-dwelling mechanical ventilation is not required for Junior Accessory Dwelling Units (JADU) when complying as an addition to an existing building
- Water heater options for additions updated for more specificity across all types.
- Duct leakage testing is required in certain HVAC duct alterations.
- HPWHs are allowed for alterations in all climate zones.
- Cool roof requirements expanded to additional climate zones for alterations.
- New roof and vented attic ceiling insulation requirements for alterations
- Revised IAQ and mechanical exhaust requirements.
- Alterations that add door areas must meet prescriptive U-factor requirements.