SnowLoadCheck

St. Joseph County, MI Roof Snow Load - 20 psf

St. Joseph County, MI: your roof's ASCE 7 snow number, in plain English

Moderate
20 psf

St. Joseph County's roofs are built to hold 20 psf of snow, the ASCE 7-22 figure a permit reviewer checks first. 17.5 psf is what the ground-load formula alone gives; St. Joseph 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.

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.

St. Joseph County at a glance

St. Joseph County by the numbers

Nationally that's #707 out of 2,758 rated counties, the top 26%; within Michigan alone, St. Joseph County ranks #68 of 70. That's 11.7 psf below Michigan's own county-average design load of 31.7 psf.

St. Joseph County, FIPS 26149, is home to 61,171 people near 41.9115°N 85.5229°W. Its 25 psf ground snow load figure is the map value; 20 psf is what a roof is actually designed for.

St. Joseph County's snowfall, most winters

41.2 in. a year: that's St. Joseph County's NOAA 1991-2020 snowfall normal, measured at THREE RIVERS, MI US (6.1 mi away). See the density guide.

Before you rely on St. Joseph County's number

Treat the St. Joseph 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. See the methodology guide.