California Climate Zone 13 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 13 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 13 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 13 is one of them.
Why Climate Zone 13 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 13 and What It Means for Your Report
Climate Zone 13 covers the southern San Joaquin Valley, including Fresno, Visalia and Bakersfield. It has some of the hottest, longest summers of any populated zone in California, while winters are cool and often foggy in the valley.
Cooling dominates the energy model in Zone 13. Window solar heat gain, glass area on west and south elevations, roof and attic design, and ducts running through hot attics can quickly use up the budget, so these are where designs usually win or lose. Efficient heat pump or air conditioning equipment, well-sealed ducts and good attic insulation are the typical levers, with winter heating a secondary but real part of the calculation.
Cities & areas in Climate Zone 13
Climate zones are assigned by exact project address — often by ZIP code — and a single city can span more than one zone. The cities named on this page are examples only; we always confirm your zone from your project address. Browse our city Title 24 pages or read how cities map to Zone 13.
California Title 24 Climate Zone 13. Your project's zone is set by its address; see the California Energy Commission's official climate zone map for boundaries.
How Zone 13 affects HVAC
The zone's climate influences how heating and cooling are weighted in the model. Current Title 24 favors heat pumps statewide. Zone 13 HVAC requirements →
How Zone 13 affects windows
U-factor and SHGC targets are influenced by the zone's climate. Zone 13 window requirements →
How Zone 13 affects insulation
Wall, roof, and floor performance is measured against the zone's energy budget. Zone 13 insulation requirements →
How Zone 13 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 13, taken from the California Energy Commission's official table, or use the climate zone ZIP code lookup.
Title 24 Guides for Climate Zone 13
Start with the Climate Zone 13 Title 24 requirements overview, then read Zone 13 HVAC requirements, Zone 13 window requirements and Zone 13 insulation requirements, the systems most affected by valley heat. The Zone 13 heat pump guide explains equipment choices, the Zone 13 ADU guide covers backyard units, and Title 24 cost in Zone 13 covers pricing. For statewide background, see California Title 24 requirements and Title 24 calculations. City guides include Fresno and Bakersfield.
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