SnowLoadCheck

Rosebud County, MT Roof Snow Load - 20 psf

Rosebud County, MT: your roof's ASCE 7 snow number, in plain English

Moderate
20 psf

Rosebud County's roofs are built to hold 20 psf of snow, the ASCE 7-22 figure a permit reviewer checks first. ASCE 7's low-slope-roof minimum (§7.3.4) raises the governing figure to 20 psf - higher than the 14 psf the ground-load formula alone would give, and the code says use the larger one.

In depth, not weight: that's roughly 44 inches of fresh, light snow, 16 inches of old, settled snow, or as little as 4 inches of solid ice - snow that heavy is rare here but ice from a freeze-thaw cycle adds up far faster than the depth suggests. This is a meaningful design load - most modern-code homes handle it fine, though an addition, a carport or a flat-roofed section can be a weak spot.

Rosebud County in numbers

Rosebud County by the numbers

Nationally that's #1,145 out of 2,758 rated counties, the top 42%; within Montana alone, Rosebud County ranks #15 of 29. 19 psf is Montana's typical county figure - Rosebud County beats it by 1 psf.

Rosebud County, FIPS 30087, is home to 8,194 people near 46.1732°N 106.6668°W. Its 20 psf ground snow load figure is the map value; 20 psf is what a roof is actually designed for.

Rosebud County's snowfall, most winters

34.6 in. a year: that's Rosebud County's NOAA 1991-2020 snowfall normal, measured at FORSYTH, MT US (6.9 mi away). See the density guide.

Before you rely on Rosebud County's number

Treat the Rosebud County figure as a starting point, not a final answer: it assumes standard occupancy, a heated structure and a moderately sheltered site, per ASCE 7-22's own defaults. Exposed terrain, an unheated building or a steeper roof all shift the real number.

For a real application, skip the county number and go straight to the ASCE 7 Hazard Tool - enter your coordinates and it returns a site-specific figure a plan reviewer will recognize. (How this figure is calculated.)