Marion County, AL Roof Snow Load - 10 psf
Marion County, AL roof snow load, translated
A typical heated home in Marion 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.
Marion County, AL: quick facts
- Design roof snow load10 psf
- Ground snow load, ASCE 7 map10 psf
- National rank#1,846 of 2,758
- Alabama rank#14 of 67
- Population29,323
- Annual snowfall, NOAA normal1.3 in.
- FIPS01093
Where Marion County ranks
#14 of 67 Alabama counties by design load, top 67% of 2,758 nationally - that's Marion County's spot. That's 4.4 psf above Alabama's own county-average design load of 5.6 psf.
FIPS 01093, population 29,323, centered near 34.1382°N 87.8816°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.
Marion County: average annual snowfall
Marion County sees about 1.3 in. of snow most winters, per the HAMILTON 3 S, AL US station's 1991-2020 NOAA normal. See the density guide.
Read this before you use Marion 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.