Title 24 Reports in Tulare County

Valley floor to Sierra crest

Zone 13 covers the great majority of the county — 34 of the 40 ZIP codes we derive for it — and it is a hot, dry, cooling-dominated valley climate. Zone 16 covers the mountain ZIP codes to the east, and it is the coldest assignment in the state.

There is no gradual transition in between. The county rises from the valley to the Sierra over a relatively short horizontal distance, so the two zones sit close together while having almost nothing in common. Zone 13 design is about rejecting heat; zone 16 design is about retaining it.

The practical consequence

This is the sharpest zone contrast in any county on this site, and it means the county name carries less information here than almost anywhere. A calculation for Visalia and one for a mountain community are not variations of the same document.

Because zone 13 dominates by volume, the default assumption for a Tulare County project is usually right — which is exactly what makes the exceptions easy to miss.

Cooling drives the valley calculation

On the zone 13 floor, glazing area and orientation, duct location and equipment efficiency carry more weight than they would on the coast. A west-facing glazed elevation that clears comfortably in a mild zone frequently will not clear here without something else compensating for it.

Example ZIP codes and their zones

Derived from the Energy Commission's ZIP-to-climate-zone table, with county membership taken from the U.S. Census Bureau's 2020 ZCTA-to-county relationship file:

• Climate zone 13 — 93221, 93257, 93274, 93277, 93291 and 29 more
• Climate zone 16 — 93208, 93262, 93265, 93633 and 2 more

ZIP codes that cross the county line

A ZIP code is a postal boundary, not a county boundary, and several here fall on both sides of one. Where that happens we do not treat the county as settling the question:

• 93527 — about 51% within Tulare County, the remainder in Kern 35% and Inyo 14%
• 93631 — about 53% within Tulare County, the remainder in Fresno 26% and Kings 21%
• 93646 — about 58% within Tulare County, the remainder in Fresno 42%
• 93238 — about 66% within Tulare County, the remainder in Kern 34%

For an address in one of these, the climate zone still comes from the ZIP code, which is assigned by the Energy Commission regardless of the county line. What the split affects is which jurisdiction issues the permit — worth confirming before a submittal.

Finding the zone for your own project

The zone is set by the project's location and confirmed from the ZIP code against the Energy Commission's published table — not from the county name and not from the nearest large town. Because Tulare County contains more than one zone, that check decides which set of numbers a report is written against.

Give us the project address and we determine the zone as part of preparing the report. It is the first thing established, because every insulation, glazing and equipment figure downstream depends on it.

City and unincorporated permitting

A project inside a city's limits is permitted by that city. A project on unincorporated land is permitted by the county instead, and the two can run different submittal processes even where the energy requirements are identical. The California Energy Code is statewide — what changes locally is the climate zone the site falls in and how the jurisdiction wants the compliance documents presented.

Climate zones in Tulare County

Tulare County contains California climate zones 13 and 16. The zone drives the insulation, glazing and equipment performance a report has to demonstrate, and it is confirmed from the project ZIP code against the Energy Commission's published table.