St. Clair County, AL Roof Snow Load - 5 psf
How much snow is too much for a roof in St. Clair County, AL?
5 psf: that's what ASCE 7-22 requires a typical heated home's roof in St. Clair County to carry. Flat and low-pitch roofs in St. Clair County are actually governed by ASCE 7's §7.3.4 minimum of 5 psf, not the 3.5 psf the ground-load formula alone would produce.
Picture it, not just weigh it: 11 in. if it's fresh powder, 4 in. once it settles, or a mere 1 in. if it's ice. A modest addition to standard roof loading. Ordinary residential construction handles this without extra bracing.
St. Clair County, AL: quick facts
- Design roof snow load5 psf
- Ground snow load, ASCE 7 map5 psf
- National rank#2,144 of 2,758
- Alabama rank#25 of 67
- Population96,927
- Annual snowfall, NOAA normal0 in.
- FIPS01115
How St. Clair County compares
5 psf ranks #2,144 of 2,758 US counties with a mapped snow load (top 78%) - and #25 of 67 in Alabama. 5.6 psf is Alabama's typical county figure - St. Clair County comes in 0.6 psf under it.
Population 96,927 (FIPS 01115), roughly 33.7195°N 86.3113°W. The 5 psf ground snow load ASCE 7-22 maps here becomes 5 psf once the code's own design factors are applied.
Typical snowfall in St. Clair County, AL
NOAA's 30-year normal for St. Clair County: 0 in. of snow a year, from the PALMERDALE, AL US station. (fresh vs. packed vs. ice explains why.)
What this St. Clair County figure assumes
This is a county-level reference figure for a typical heated home built to Risk Category II (ordinary residential), on a partially exposed lot - the assumptions ASCE 7-22 itself treats as the default case. A steeper roof, a fully exposed hilltop lot, an unheated structure, or a higher risk category all change the actual number.
St. Clair County's permit office wants an address-specific figure, not this county average - the ASCE 7 Hazard Tool is free, takes under a minute, and outputs a PDF most reviewers accept. (How this figure is calculated.)