Platte County, WY Roof Snow Load - 20 psf
How much snow is too much for a roof in Platte County, WY?
20 psf: that's what ASCE 7-22 requires a typical heated home's roof in Platte County to carry. The physics-based figure alone would be 14 psf, but ASCE 7's own low-slope minimum (§7.3.4) sets a floor of 20 psf for flat and low-pitch roofs here, which is the number that actually governs.
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.
Platte County, WY: quick facts
- Design roof snow load20 psf
- Ground snow load, ASCE 7 map20 psf
- National rank#1,137 of 2,758
- Wyoming rank#7 of 18
- Population8,512
- Annual snowfall, NOAA normal39.9 in.
- FIPS56031
How Platte County compares
20 psf ranks #1,137 of 2,758 US counties with a mapped snow load (top 41%) - and #7 of 18 in Wyoming. 17.5 psf is Wyoming's typical county figure - Platte County beats it by 2.5 psf.
Population 8,512 (FIPS 56031), roughly 42.1316°N 104.954°W. The 20 psf ground snow load ASCE 7-22 maps here becomes 20 psf once the code's own design factors are applied.
Typical snowfall in Platte County, WY
NOAA's 30-year normal for Platte County: 39.9 in. of snow a year, from the WHEATLAND 4 N, WY US station. (fresh vs. packed vs. ice explains why.)
What this Platte 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.
Platte 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.)