Codes and Design Criteria
- Building Codes
- Municipal Codes
- Snow Loads
- Wind Loads
- Flood Hazards
- Climate Zone
- Winter Design
- Ice Shield Underlayment
- Air Freezing Index
- Mean Annual Temp
Adopted Building Codes
Effective July 1, 2023:
- 2021 International Building Code, including appendices C & J
- 2021 International Residential Code, including appendix AQ
- Except residential provisions of Chapter 11, Energy Efficiency.
- 2021 International Plumbing Code
- 2021 International Mechanical Code
- 2021 International Fuel Gas Code
- 2020 National Electrical Code issued by the National Fire Protection Association (NFPA)
- 2015 International Energy Conservation Code (residential)
- 2021 International Energy Conservation Code (commercial)
- 2021 International Existing Building Code
- 2021 International Swimming Pool & Spa
- 2006 International Wildland-Urban Interface Code
- Manufactured Home:
- Subsection 15A-2-104(2), the HUD Code
- Subsection 15A-2-104(1), Appendix AE of the 2021 International Residential Code
- Subsection 15A-2-104(1), 2005 NFPA 225 Model Manufactured Home Installation Standard, issued by the NFPA
- Historic Buildings:
- Subsection (3) for standard guidelines pertaining to plaster on a historic property, as defined in Section 9-8-302, the US Department of the Interior Secretary's Standards for Rehabilitation and Guidelines for Rehabilitating Historic Buildings
- Adopted per the
- Ground Snow Loads: The actual snow loads vary depending upon elevation. For all projects located at, or below, 4,239 feet mean sea level the ground snow load (Pg) shall be a minimum of 28 pounds per square foot. For elevations above 4,239 feet mean sea level please visit https://utahsnowload.usu.edu as referenced in Section 15A of Utah’s “State Construction and Fire Codes Act”.
- Roof Snow Loads: Shall be determined per Chapter 7 of ASCE 7-16.
- Seismic Snow: At locations where the roof snow load exceeds 30psf a percentage of the snow load must be considered in the effective seismic weight of the structure per Section 15A-3-107 of Utah’s “State Construction and Fire Codes Act”.
- Speed: All wind speeds listed below are 3-second gusts at 33 feet above the ground.
- Residential: 115 mph
- Commercial (see IBC Figures 1609.3(1-4):
- Risk Category I = 100 mph
- Risk Category II = 105 mph
- Risk Category III = 110 mph
- Risk Category IV = 115 mph
- Exposure: Site-specific (per Chapter 26 of ASCE 7-16). Typically, “B” or “C”.
- Seismic Design Category:
- Residential: D2
- Commercial: D
- Site-specific: Because ground motions tend to vary substantially throughout the city, the mapped spectral accelerations (SS & S1) should be obtained by considering the site-specific address or latitude and longitude values and obtaining the ground motions from the Applied Technology Council’s “ATC Hazards by Location” tool (https://hazards.atcouncil.org/).
- Site-Specific Parameters (unless ASCE 7 exceptions are met):
- S1 ≥ 0.2g and Site Class ‘D or E’ → A ground motion hazard analysis (GMHA) must be provided.
- SS ≥ 1.0g and Site Class ‘E’ → A ground motion hazard analysis (GMHA) must be provided.
- Site Class ‘F’ → A site response analysis (SRA) must be provided.
- Frost Depth: 30 inches. This may increase at higher elevations.
- Site Class: Site-specific. For projects not requiring a geotechnical report (see below) Site Class ‘D’ can be assumed per Section 20.1 of ASCE 7-16 but ground motions must be adjusted per IBC 1613.2.3.
- Allowable Bearing Pressures:
- Foundation pressure: 1,500psf, per IRC Table R401.4.1 and IBC Table 1806.2.
- Lateral pressure: 100psf/f, per IBC Table 1806.2.
- The above-listed values are the maximum allowable values unless listed otherwise by a site-specific geotechnical report complying with IBC 1803.6 and IBC 1803.5.5, as applicable.
- Site-specific Geotechnical Report:
- General: All geotechnical reports submitted for permit issuance must be dated no later than two years from the permit application date. Outdated reports must be accompanied by a letter from a qualified geotechnical engineer stating that the report requirements are still valid or stating what items may have changed.
- Residential: Residential projects meeting one or more of the following requirements must provide a site-specific geotechnical report meeting the requirements of IBC 1803.6:
- Where the building footprint is greater than 3,000 square feet or has a gross square footage of 6,000 square feet or greater; or
- Where the grade supporting the structure has a slope equal to or greater than 20 percent; or
- Where the building is to be built on a lot in which a previous structure once existed.
- Commercial: All commercial projects require a site-specific soil report meeting the requirements of IBC 1803.6 and IBC 1803.5.5, as applicable. Additions to existing facilities of less than 3,000 square feet are exempt from this requirement.
- Flood Hazard Areas:
- Residential: Buildings and structures located in flood hazard areas (i.e. Flood Zones A or V) must comply with IRC R322.
- Commercial: Buildings and structures located in flood hazard areas must comply with IBC 1612, Chapter 5 of ASCE 7-16 and ASCE 24-14.
- Floodways: Buildings and structures located in identified floodways must be designed and constructed in accordance with ASCE 24-14.
- Interactive Flood Zone Map: Available at the following WEB LINK.
The average annual rainfall is 16 inches.
None to Slight
WINTER DESIGN TEMP
ICE SHIELD UNDERLAYMENT
AIR FREEZING INDEX
MEAN ANNUAL TEMP
- List current codes w/ link to State Amendments
- USU Snow Load site
- Wind Loads
- Climate Zone
- ASHRAE information
- Floodplain map