Wirt County, WV Roof Snow Load - 20 psf
Wirt County, WV roof snow load, translated
A typical heated home in Wirt County is designed to carry 20 pounds per square foot of snow on its roof, per ASCE 7-22. The physics-based figure alone would be 17.5 psf, but ASCE 7's own low-slope minimum (§7.3.4) sets a floor of 20 psf for flat and low-pitch roofs here, which is the number that actually governs.
On a roof that means 44 in. of fresh snow, 16 in. once it packs down, or 4 in. of solid ice - three very different piles for the same load. Modern-code homes carry a load like this without issue; an older addition, a carport, or any flat-roofed section is where it is worth checking first.
Wirt County at a glance
- Design roof snow load20 psf
- Ground snow load, ASCE 7 map25 psf
- National rank#1,219 of 2,758
- West Virginia rank#34 of 34
- Population4,924
- Annual snowfall, NOAA normal24.2 in.
- FIPS54105
Where Wirt County ranks
#34 of 34 West Virginia counties by design load, top 44% of 2,758 nationally - that's Wirt County's spot. Wirt County's figure lands almost exactly on West Virginia's own county-average of 20 psf.
FIPS 54105, population 4,924, centered near 39.02°N 81.383°W. ASCE 7's underlying ground snow load here is 25 psf before the code's exposure and importance factors bring it to the 20 psf design figure above.
Wirt County: average annual snowfall
Wirt County sees about 24.2 in. of snow most winters, per the SANDYVILLE 9 NE, WV US station's 1991-2020 NOAA normal. See the density guide.
Read this before you use Wirt County's figure
The figure above assumes the case ASCE 7-22 treats as typical: a heated, ordinary-occupancy home on a partially exposed site. Change any of those - exposure, heating, roof pitch, occupancy category - and the real design number moves.
A building permit needs the number at your exact address, not the county average - the free ASCE 7 Hazard Tool returns that from your coordinates in about a minute and produces a PDF a plan reviewer will accept. Details: the calculation guide.