Union County, SC Roof Snow Load - 10 psf
Union County, SC roof snow load, translated
A typical heated home in Union County is designed to carry 10 pounds per square foot of snow on its roof, per ASCE 7-22. 7 psf is what the ground-load formula alone gives; Union County's 10 psf low-slope minimum (§7.3.4) beats it, so that figure is the one that governs on flat and low-pitch roofs.
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. A modest addition to standard roof loading. Ordinary residential construction handles this without extra bracing.
Snow on Union County's roofs right now?
Union County in numbers
- Design roof snow load10 psf
- Ground snow load, ASCE 7 map10 psf
- National rank#1,863 of 2,758
- South Carolina rank#28 of 46
- Population26,678
- Annual snowfall, NOAA normal1.9 in.
- FIPS45087
Where Union County ranks
#28 of 46 South Carolina counties by design load, top 68% of 2,758 nationally - that's Union County's spot. 8.8 psf is South Carolina's typical county figure - Union County beats it by 1.2 psf.
FIPS 45087, population 26,678, centered near 34.6904°N 81.6159°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.
Union County: average annual snowfall
Union County sees about 1.9 in. of snow most winters, per the UNION 8 S, SC US station's 1991-2020 NOAA normal. See the density guide.
Read this before you use Union 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.