Lewis County, TN Roof Snow Load - 10 psf
What ASCE 7 says about snow load in Lewis County
That's Lewis County's design roof snow load per ASCE 7-22, for a typical heated single-family home - the number a permit reviewer starts from. The physics-based figure alone would be 7 psf, but ASCE 7's own low-slope minimum (§7.3.4) sets a floor of 10 psf for flat and low-pitch roofs here, which is the number that actually governs.
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.
Snow on Lewis County's roofs right now?
Lewis County at a glance
- Design roof snow load10 psf
- Ground snow load, ASCE 7 map10 psf
- National rank#1,965 of 2,758
- Tennessee rank#84 of 95
- Population13,418
- Annual snowfall, NOAA normal2.1 in.
- FIPS47101
Where Lewis County's figure sits nationally
Out of 2,758 rated US counties, Lewis County sits at #1,965, the top 71% nationally - #84 of 95 within Tennessee. 10.3 psf is Tennessee's typical county figure - Lewis County comes in 0.3 psf under it.
Near 35.5232°N 87.497°W, FIPS 47101: Lewis County counts 13,418 residents and a 10 psf map value, which the code's own factors turn into 10 psf.
How much it actually snows in Lewis County
Most winters bring Lewis County roughly 2.1 in. of snow - NOAA's normal at LINDEN WTP, TN US, 20.1 mi off. (fresh vs. packed vs. ice explains why.)
Read this before you rely on it
Lewis 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 Lewis County's county-wide figure. Details: the calculation guide.