Richland County, MT Roof Snow Load - 20 psf
How much snow is too much for a roof in Richland County, MT?
20 psf: that's what ASCE 7-22 requires a typical heated home's roof in Richland County to carry. ASCE 7's low-slope-roof minimum (§7.3.4) raises the governing figure to 20 psf - higher than the 17.5 psf the ground-load formula alone would give, and the code says use the larger one.
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.
Richland County, MT: quick facts
- Design roof snow load20 psf
- Ground snow load, ASCE 7 map25 psf
- National rank#1,086 of 2,758
- Montana rank#12 of 29
- Population11,028
- Annual snowfall, NOAA normal39.3 in.
- FIPS30083
How Richland County compares
20 psf ranks #1,086 of 2,758 US counties with a mapped snow load (top 39%) - and #12 of 29 in Montana. Montana counties average 19 psf; Richland County runs 1 psf higher than that.
Population 11,028 (FIPS 30083), roughly 47.7856°N 104.5634°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 Richland County, MT
NOAA's 30-year normal for Richland County: 39.3 in. of snow a year, from the WILLISTON EXP FARM, ND US station. 45.3 mi is a real gap between Richland County and its nearest reporting station, so local snowfall can diverge from this figure, especially near elevation changes. (fresh vs. packed vs. ice explains why.)
What this Richland 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.
Richland 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.