Knox County, TN Roof Snow Load - 10 psf
What ASCE 7 says about snow load in Knox County
That's Knox County's design roof snow load per ASCE 7-22, for a typical heated single-family home - the number a permit reviewer starts from. §7.3.4's low-slope minimum of 10 psf is what actually governs on a flat or low-pitch roof here - higher than the 7 psf the base ground-load formula gives.
Converted to something you can actually eyeball on a roof: about 22 in. of fresh powder, 8 in. once it settles and packs down, or just 2 in. if it's turned to ice. A modest addition to standard roof loading. Ordinary residential construction handles this without extra bracing.
Knox County in numbers
- Design roof snow load10 psf
- Ground snow load, ASCE 7 map10 psf
- National rank#1,656 of 2,758
- Tennessee rank#8 of 95
- Population506,748
- Annual snowfall, NOAA normal4.6 in.
- FIPS47093
Where Knox County's figure sits nationally
Out of 2,758 rated US counties, Knox County sits at #1,656, the top 60% nationally - #8 of 95 within Tennessee. Tennessee counties average 10.3 psf; Knox County runs 0.3 psf lower than that.
Near 35.9927°N 83.9377°W, FIPS 47093: Knox County counts 506,748 residents and a 10 psf map value, which the code's own factors turn into 10 psf.
How much it actually snows in Knox County
Most winters bring Knox County roughly 4.6 in. of snow - NOAA's normal at KNOXVILLE MCGHEE TYSON AP, TN US, 12.4 mi off. (fresh vs. packed vs. ice explains why.)
Read this before you rely on it
Knox County's number above is ASCE 7-22's default case, not a custom calculation: ordinary residential occupancy, heated, sited on ground that's neither fully sheltered nor fully exposed. Any one of those changing - pitch, exposure, heating, occupancy - moves the real figure.
Nothing here substitutes for an address-level number. Get one free, in about a minute, from the ASCE 7 Hazard Tool using your own coordinates rather than Knox County's county-wide figure. (How this figure is calculated.)