Swain County, NC Roof Snow Load - 10 psf
Swain County, NC roof snow load, translated
A typical heated home in Swain County is designed to carry 10 pounds per square foot of snow on its roof, per ASCE 7-22. ASCE 7's low-slope-roof minimum (§7.3.4) raises the governing figure to 10 psf - higher than the 7 psf the ground-load formula alone would give, and the code says use the larger one.
On a roof that means 22 in. of fresh snow, 8 in. once it packs down, or 2 in. of solid ice - three very different piles for the same load. This is a modest add-on to standard roof loading - ordinary residential construction carries it without extra bracing.
Swain County at a glance
- Design roof snow load10 psf
- Ground snow load, ASCE 7 map10 psf
- National rank#1,959 of 2,758
- North Carolina rank#89 of 100
- Population13,945
- Annual snowfall, NOAA normal7.7 in.
- FIPS37173
Where Swain County ranks
#89 of 100 North Carolina counties by design load, top 71% of 2,758 nationally - that's Swain County's spot. That's 2.9 psf below North Carolina's own county-average design load of 12.9 psf.
FIPS 37173, population 13,945, centered near 35.5688°N 83.4656°W. ASCE 7's underlying ground snow load here is 10 psf before the code's exposure and importance factors bring it to the 10 psf design figure above.
Swain County: average annual snowfall
Swain County sees about 7.7 in. of snow most winters, per the GATLINBURG 2 SW, TN US station's 1991-2020 NOAA normal. See the density guide.
Read this before you use Swain 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. (How this figure is calculated.)