Salt Lake County is in IECC Climate Zone 5B (Cool - Dry). Get accurate Manual J load calculations with official ASHRAE design temperatures for Salt Lake County.
Salt Lake County, Utah is classified under IECC Climate Zone 5B (Cool - Dry), a heating-dominated region with dry moisture conditions. With 73 ZIP codes and 1 communities, every HVAC installation in Salt Lake County must use the ASHRAE design temperatures of 11°F (99% winter heating) and 96°F (1% summer cooling) for accurate Manual J load calculations.
As a heating-dominated zone, Salt Lake County requires robust insulation — a minimum of R-20 in walls, R-49 in ceilings, and R-30 in floors. Windows must meet a U-factor of 0.3 or lower. These requirements ensure homes maintain comfort during the coldest 11°F design conditions.
Minimum insulation R-values and window performance for Climate Zone 5B in Salt Lake County, UT.
| Building Component | Minimum Requirement | Unit |
|---|---|---|
| Ceiling / Attic Insulation | R-49 | R-value |
| Wall Insulation | R-20 | R-value |
| Floor Insulation | R-30 | R-value |
| Window U-Factor | 0.3 | BTU/hr-ft²-°F |
| Window SHGC | 0.4 | Coefficient |
| Air Infiltration | 0.15 | ACH50 |
Climate Zone 5B requires precise load calculations. Upload your Salt Lake County blueprint and get a professional Manual J report in 60 seconds— first report is FREE. Pre-loaded with Salt Lake County's exact design temperatures (11°F winter / 96°F summer).
Enter your ZIP code to confirm it's in Salt Lake County and get climate zone details.
Official ASHRAE design temperatures for Salt Lake County, UT, used for accurate Manual J load calculations.
Minimum insulation and window requirements for Salt Lake County per IECC 2021 energy code.
Climate Zone 5B: Cool - Dry - Heating-dominated with cold, dry winters and warm summers. High heating loads in winter, moderate cooling needs.
1 cities and communities in Salt Lake County share Climate Zone 5B requirements.
Compare climate zones with other counties in Utah. Different zones require different HVAC equipment sizing.
Upload your Salt Lake County blueprint and get a professional Manual J load calculation using official Zone 5B design temperatures. First report is FREE.
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