Richland County, SC Roof Snow Load - 10 psf
Richland County, SC: your roof's ASCE 7 snow number, in plain English
Richland County's roofs are built to hold 10 psf of snow, the ASCE 7-22 figure a permit reviewer checks first. 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.
In depth, not weight: that's roughly 22 inches of fresh, light snow, 8 inches of old, settled snow, or as little as 2 inches of solid ice - snow that heavy is rare here but ice from a freeze-thaw cycle adds up far faster than the depth suggests. A modest addition to standard roof loading. Ordinary residential construction handles this without extra bracing.
Already snow on the roof in Richland County?
Richland County in numbers
- Design roof snow load10 psf
- Ground snow load, ASCE 7 map10 psf
- National rank#1,658 of 2,758
- South Carolina rank#2 of 46
- Population430,651
- Annual snowfall, NOAA normal0.4 in.
- FIPS45079
Richland County by the numbers
Nationally that's #1,658 out of 2,758 rated counties, the top 60%; within South Carolina alone, Richland County ranks #2 of 46. 8.8 psf is South Carolina's typical county figure - Richland County beats it by 1.2 psf.
Richland County, FIPS 45079, is home to 430,651 people near 34.0291°N 80.898°W. Its 10 psf ground snow load figure is the map value; 10 psf is what a roof is actually designed for.
Richland County's snowfall, most winters
0.4 in. a year: that's Richland County's NOAA 1991-2020 snowfall normal, measured at SANDHILL RSCH - ELGIN, SC US (7.2 mi away). See the density guide.
Before you rely on Richland County's number
Treat the Richland County figure as a starting point, not a final answer: it assumes standard occupancy, a heated structure and a moderately sheltered site, per ASCE 7-22's own defaults. Exposed terrain, an unheated building or a steeper roof all shift the real number.
For a real application, skip the county number and go straight to the ASCE 7 Hazard Tool - enter your coordinates and it returns a site-specific figure a plan reviewer will recognize. (How this figure is calculated.)