SnowLoadCheck

Lancaster County, SC Roof Snow Load - 10 psf

Lancaster County, SC roof snow load, translated

Light
10 psf

A typical heated home in Lancaster 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; Lancaster 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. Standard residential construction handles a load this size without extra bracing; it is a modest addition on top of ordinary roof loading.

Lancaster County at a glance

Where Lancaster County ranks

#11 of 46 South Carolina counties by design load, top 62% of 2,758 nationally - that's Lancaster County's spot. South Carolina counties average 8.8 psf; Lancaster County runs 1.2 psf higher than that.

FIPS 45057, population 111,652, centered near 34.6868°N 80.7037°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.

Lancaster County: average annual snowfall

Lancaster County sees about 0.5 in. of snow most winters, per the GREAT FALLS, SC US station's 1991-2020 NOAA normal. See the density guide.

Read this before you use Lancaster 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. See the methodology guide.