California Climate Zone 1 is one of the 16 official climate zones the California Energy Commission uses to set Title 24 energy budgets. Title 24 is a statewide California energy code. Climate Zone 1 does not have its own separate rules — the same statewide standards apply, with the energy budget calibrated to this zone's climate. Your project's exact requirements are determined when your specific address is modeled in CEC-approved compliance software.
What Climate Zone 1 means
Each of California's 16 zones reflects distinct temperature, humidity, and solar conditions, and each has its own energy budget under Title 24. Climate Zone 1 is one of them.
Why Climate Zone 1 matters for Title 24
Although the standards are statewide, the budget your design must meet is calibrated to the zone — which can shift the emphasis between insulation, HVAC, windows, and solar. The exact targets are determined when your address is modeled.
The Climate in Zone 1 and What It Means for Your Report
Climate Zone 1 covers California's far north coast. It is a cool, damp marine climate: summers stay mild, fog is common, and homes need some heat for much of the year, while air conditioning is rarely a major load. That makes Zone 1 one of the most heating-dominated zones in the state outside the mountains.
In the energy model, heating carries most of the weight. Well-insulated and well-sealed walls, ceilings and raised floors, windows that limit heat loss, and an efficient heat pump sized for a long heating season usually decide whether a design complies. Water heating is a steady year-round load here too, so the choice of water heater can noticeably move the result.
Cities & areas in Climate Zone 1
Climate zones are assigned by exact project address — often by ZIP code — and a single city can span more than one zone. Rather than publish an unverified city list, we confirm your zone from your project address. Browse our city Title 24 pages or read how cities map to Zone 1.
California Title 24 Climate Zone 1. Your project's zone is set by its address; see the California Energy Commission's official climate zone map for boundaries.
How Zone 1 affects HVAC
The zone's climate influences how heating and cooling are weighted in the model. Current Title 24 favors heat pumps statewide. Zone 1 HVAC requirements →
How Zone 1 affects windows
U-factor and SHGC targets are influenced by the zone's climate. Zone 1 window requirements →
How Zone 1 affects insulation
Wall, roof, and floor performance is measured against the zone's energy budget. Zone 1 insulation requirements →
How Zone 1 affects solar & heat pumps
Solar PV is required for most new low-rise residential statewide, with PV size set by your project; heat pumps are favored under current code. Solar & battery → · Heat pumps →
Common project types
Looking for a specific address? See every city and ZIP code in Climate Zone 1, taken from the California Energy Commission's official table, or use the climate zone ZIP code lookup.
Title 24 Guides for Climate Zone 1
Start with the Climate Zone 1 Title 24 requirements overview, then go deeper on insulation in Zone 1, Zone 1 window requirements and heat pumps in Zone 1, the areas that matter most in a cool coastal climate. Building a backyard unit? The Zone 1 ADU guide covers what the report needs, and Title 24 cost in Zone 1 explains pricing. For the statewide rules, see California Title 24 requirements and how Title 24 calculations work. For the wider region, see our Northern California Title 24 page.
Climate zones follow the project address, not just the city name, and one city can straddle two zones. We confirm the exact zone from your address or ZIP code when we model the project; you can also check it yourself with our California climate zone lookup.
Title 24 pricing
- ADU — from $199
- Residential — from $245
- Multifamily — from $345
Standard turnaround: 2–3 business days. Rush (next business day): +$49 ADU / +$99 Residential / +$149 Multifamily. Super Rush (same day — typically completed within a few hours): +$150, subject to availability. Every report includes two revisions. See our pricing page.
What we need
- Architectural plans (PDF)
- Project address (this determines your climate zone)
- Scope of work
- Contact information
- Any plan-check comments (if available)
What we deliver
- Complete Title 24 energy report
- CF1R documentation (LMCC when applicable)
- CHEERS registration completed
- Professionally signed, permit-ready PDF package
- Two Revisions Included