Smyth County, VA Roof Snow Load - 20 psf
What ASCE 7 says about snow load in Smyth County
That's Smyth County's design roof snow load per ASCE 7-22, for a typical heated single-family home - the number a permit reviewer starts from. 14 psf is what the ground-load formula alone gives; Smyth County's 20 psf low-slope minimum (§7.3.4) beats it, so that figure is the one that governs on flat and low-pitch roofs.
Converted to something you can actually eyeball on a roof: about 44 in. of fresh powder, 16 in. once it settles and packs down, or just 4 in. if it's turned to ice. A meaningful design load. Most homes built to modern code handle it, but additions, carports, and flat-roofed sections are worth a second look.
Smyth County, VA: quick facts
- Design roof snow load20 psf
- Ground snow load, ASCE 7 map20 psf
- National rank#867 of 2,758
- Virginia rank#43 of 110
- Population29,137
- Annual snowfall, NOAA normal8.5 in.
- FIPS51173
Where Smyth County's figure sits nationally
Out of 2,758 rated US counties, Smyth County sits at #867, the top 31% nationally - #43 of 110 within Virginia. Virginia counties average 18.3 psf; Smyth County runs 1.7 psf higher than that.
Near 36.8423°N 81.5398°W, FIPS 51173: Smyth County counts 29,137 residents and a 20 psf map value, which the code's own factors turn into 20 psf.
How much it actually snows in Smyth County
Most winters bring Smyth County roughly 8.5 in. of snow - NOAA's normal at TROUT DALE 3 SSE, VA US, 15 mi off. (fresh vs. packed vs. ice explains why.)
Read this before you rely on it
Smyth 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 Smyth County's county-wide figure. (How this figure is calculated.)