California Title 24 (Part 6): The Building Energy Efficiency Standards Explained

Title 24, Part 6 of the California Code of Regulations (CCR) is the nation’s most stringent building energy code. Updated every three years by the California Energy Commission (CEC), the 2022 edition (effective Jan 1, 2023) pushes toward the state’s 2045 carbon-neutrality goal.

Core Pillars (2022 Standards)

1. Building Envelope

• High-performance attics (R-38 ceiling + radiant barrier or R-30 + duct encapsulation).
• Wall insulation: 2x6 @ R-21 or 2x4 + continuous exterior R-5 (climate zones 1–16 vary).
• Windows: Max U-factor 0.30, max SHGC 0.23 (CZ 2,4,6–15); dynamic glazing credits.
• Quality Insulation Installation (QII) mandatory third-party verification.

2. HVAC & Water Heating

• Heat pumps prescriptive baseline for space heating (electric resistance banned in new construction).
• HSPF2 ≥ 7.5, SEER2 ≥ 14.3 (split systems).
• Duct leakage ≤ 5% (tested), buried ducts ≥ R-13.
• Water heating: HPWH (heat pump water heater) prescriptive for single-family; gas tankless allowed with solar thermal offset.

3. Lighting

• All high-efficacy (LED); manual-on/auto-off sensors in most rooms.
• Power density limits: 0.45 W/ft² (residential), 0.65 W/ft² (non-residential).
• Outdoor: motion/photocell controls, BUG ratings.

4. Solar Photovoltaic (PV) & Battery Storage

• Mandatory PV for all new low-rise residential (since 2020). 2022 adds: Battery storage readiness (raceway, panel space, disconnect) + PV + battery sizing credits for compliance.
• Non-residential: PV + battery prescriptive for many building types.

5. Ventilation & IAQ

• ASHRAE 62.2 continuous mechanical ventilation (HRV/ERV encouraged).
• MERV 13 filters mandatory (forced-air systems).
• Kitchen range hood capture efficiency ≥ 75% (tested).

6. Compliance Pathways

1. Prescriptive: Checklist—simplest, least flexible.
2. Performance (EnergyPro, CBECC-Res/Com): Trade-offs allowed (e.g., better windows for less PV).
3. EDR (Energy Design Rating): Two scores—EDR1 (source energy) & EDR2 (TDV energy). Must beat standard design budget.

7. Commissioning & Documentation

• Cx required for non-res >10k ft²; HERS verification for residential (envelope, HVAC, IAQ, PV).
• CF-1R (design), CF-2R (install), CF-3R (verification) forms uploaded to CEC registry.

Why It Matters

Buildings = 25% of CA GHG emissions. Title 24 drives market transformation: heat-pump adoption, grid-interactive buildings, embodied carbon tracking (coming in 2025 cycle). Compliance adds ~$8–12k upfront for a new home but yields $30k+ lifetime energy savings (CEC est.).