Montgomery County, VA Roof Snow Load - 20 psf
How much snow is too much for a roof in Montgomery County, VA?
20 psf: that's what ASCE 7-22 requires a typical heated home's roof in Montgomery County to carry. 17.5 psf is what the ground-load formula alone gives; Montgomery County's 20 psf low-slope minimum (§7.3.4) beats it, so that figure is the one that governs on flat and low-pitch roofs.
Picture it, not just weigh it: 44 in. if it's fresh powder, 16 in. once it settles, or a mere 4 in. if it's ice. A meaningful design load. Most homes built to modern code handle it, but additions, carports, and flat-roofed sections are worth a second look.
Montgomery County in numbers
- Design roof snow load20 psf
- Ground snow load, ASCE 7 map25 psf
- National rank#655 of 2,758
- Virginia rank#22 of 110
- Population98,998
- Annual snowfall, NOAA normal24.7 in.
- FIPS51121
How Montgomery County compares
20 psf ranks #655 of 2,758 US counties with a mapped snow load (top 24%) - and #22 of 110 in Virginia. 18.3 psf is Virginia's typical county figure - Montgomery County beats it by 1.7 psf.
Population 98,998 (FIPS 51121), roughly 37.1755°N 80.3878°W. The 25 psf ground snow load ASCE 7-22 maps here becomes 20 psf once the code's own design factors are applied.
Typical snowfall in Montgomery County, VA
NOAA's 30-year normal for Montgomery County: 24.7 in. of snow a year, from the BLACKSBURG NWSO, VA US station. (fresh vs. packed vs. ice explains why.)
What this Montgomery 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.
Montgomery 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. See the methodology guide.