Polk County, NC Roof Snow Load - 15 psf
Polk County, NC roof snow load, translated
A typical heated home in Polk County is designed to carry 15 pounds per square foot of snow on its roof, per ASCE 7-22. §7.3.4's low-slope minimum of 15 psf is what actually governs on a flat or low-pitch roof here - higher than the 10.5 psf the base ground-load formula gives.
On a roof that means 33 in. of fresh snow, 12 in. once it packs down, or 3 in. of solid ice - three very different piles for the same load. A meaningful design load. Most homes built to modern code handle it, but additions, carports, and flat-roofed sections are worth a second look.
Polk County, NC: quick facts
- Design roof snow load15 psf
- Ground snow load, ASCE 7 map15 psf
- National rank#1,466 of 2,758
- North Carolina rank#45 of 100
- Population20,320
- Annual snowfall, NOAA normal3.1 in.
- FIPS37149
Where Polk County ranks
#45 of 100 North Carolina counties by design load, top 53% of 2,758 nationally - that's Polk County's spot. That's 2.1 psf above North Carolina's own county-average design load of 12.9 psf.
FIPS 37149, population 20,320, centered near 35.2779°N 82.1676°W. ASCE 7's underlying ground snow load here is 15 psf before the code's exposure and importance factors bring it to the 15 psf design figure above.
Polk County: average annual snowfall
Polk County sees about 3.1 in. of snow most winters, per the LAKE LURE 2, NC US station's 1991-2020 NOAA normal. See the density guide.
Read this before you use Polk 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.