Walker County, AL Roof Snow Load - 10 psf
Walker County, AL roof snow load, translated
A typical heated home in Walker County is designed to carry 10 pounds per square foot of snow on its roof, per ASCE 7-22. §7.3.4's low-slope minimum of 10 psf is what actually governs on a flat or low-pitch roof here - higher than the 7 psf the base ground-load formula gives.
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.
Walker County in numbers
- Design roof snow load10 psf
- Ground snow load, ASCE 7 map10 psf
- National rank#1,750 of 2,758
- Alabama rank#8 of 67
- Population65,260
- Annual snowfall, NOAA normal0.6 in.
- FIPS01127
Where Walker County ranks
#8 of 67 Alabama counties by design load, top 63% of 2,758 nationally - that's Walker County's spot. Alabama counties average 5.6 psf; Walker County runs 4.4 psf higher than that.
FIPS 01127, population 65,260, centered near 33.7916°N 87.3011°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.
Walker County: average annual snowfall
Walker County sees about 0.6 in. of snow most winters, per the JASPER, AL US station's 1991-2020 NOAA normal. See the density guide.
Read this before you use Walker 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.