2025 Applicable Codes and Standards
The 2025 California Building Standards Code (Cal. Code Regs., Title 24) published July 1, 2025, is effective January 1, 2026, as amended by Santa Cruz County. Supplement and emergency standard compliance is required upon effective dates. Further information is available through the Building Standards Commission.
2025 California Administrative Code | Part 1
2025 California Building Code (amended 2024 International Building Code) | Part 2
2025 California Residential Code (amended 2024 International Residential Code) | Part 2.5
2025 California Electrical Code (amended 2023 National Electrical Code (NFPA 70)) | Part 3
2025 California Mechanical Code (amended 2024 Uniform Mechanical Code) | Part 4
2025 California Plumbing Code (amended 2024 Uniform Plumbing Code) | Part 5
2025 California Energy Code | Part 6
2025 California Wildland-Urban Interface Code (amended 2024 IWUIC) | Part 7
2025 California Historical Building Code | Part 8
2025 California Fire Code (amended 2024 International Fire Code) | Part 9
2025 California Existing Code (amended 2024 International Existing Building Code) | Part 10
2025 California Green Building Standards | Part 11
2025 California Referenced Standards Code | Part 12
California Building Standards Codes
Seismic
Seismic Design Categories, SDC, are based on specific site locations. Values for spectral response accelerations, S1 and SS, and design spectral response accelerations, SD1 and SDS, may be determined using an online tool below. These values, along with the risk category (most buildings in Santa Cruz County will be Risk Category I, II or III, with residences as Risk Category II), will determine the SDC. Most of Santa Cruz County will be SDC D or E. Unless a geotechnical report determines otherwise, the default site conditions shall be the worst case of site class C, CD and D as required by Section 11.4.2.1 of ASCE 7-22. Where Site Class DE, E or F soils are present, a geotechnical report is required, and the seismic design category shall be determined in accordance with ASCE 7-22. For structures required to have a structural analysis (non-conventional), See ASCE Standard 7-22, Chapter 11, for complete Seismic Design Criteria.
SEAOC/OSHPD Tool
ASCE 7 Hazard Tool
Wind
Basic wind speed, V (3 second gust), is 90 mph for Risk Category II buildings (most buildings). Santa Cruz County has various exposure categories, so the design must be site specific. Exposure categories B (urban and suburban areas), C (open terrain with scattered obstructions or areas that are not Exposure B or D) or D (unobstructed areas and ocean front areas) all exist in Santa Cruz County. For structures required to have a structural analysis (non-conventional), See CBC 1609 or ASCE Standard 7-22, Chapter 26, for complete Wind Design Criteria.
ASCE 7 Hazard Tool
Wildland-Urban Interface
Fire Hazard Severity Zones designated as a State Responsibility Areas (SRA), or Local Responsibility Areas (LRA) designated as High or Very High, shall comply with the Materials and Construction Methods for Exterior Wildfire Exposure. Please see Wildland Urban Interface (WUI) Codes and Standards for the adopted codes and submittal requirements.
Climate Zone & Energy Standards
Applicants must evaluate two completely different sets of building parameters within Santa Cruz County independently based on their project scope:
- California Energy Code Compliance (Title 24, Part 6): The California Energy Commission splits Santa Cruz County geographically between Climate Zone 3 and Climate Zone 4. Because minimum performance requirements change based on this division, applicants must use their exact project site parameters. Use the official interactive CEC EZ Building Climate Zone Finder to verify your parcel's energy zone prior to submitting energy compliance documents, and review local information on the Energy Standards page.
- Structural, Weathering & Wall Design Criteria (Title 24, Parts 2 & 2.5): Distinct from local California energy targets, general building envelope, moisture, lath/plaster, and structural criteria are uniform throughout the county. Under national and international building standards, the entire County of Santa Cruz is classified as Marine Zone 3C (Warm - Marine) per CRC Section R301.2 and CBC Chapter 16. Under CRC Table R301.2(1), the county is designated a "Negligible" Weathering Region (freeze/thaw) and a "Very Heavy" Termite Damage Region; corresponding commercial building provisions for these environmental criteria are governed under CBC Chapter 14 for exterior walls, Chapter 19 for concrete weathering, and Section 2304.12 for wood termite protection.