Lapeer County, MI Roof Snow Load - 20 psf
Lapeer County, MI: your roof's ASCE 7 snow number, in plain English
Lapeer County's roofs are built to hold 20 psf of snow, the ASCE 7-22 figure a permit reviewer checks first. The physics-based figure alone would be 17.5 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.
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. A meaningful design load. Most homes built to modern code handle it, but additions, carports, and flat-roofed sections are worth a second look.
Lapeer County at a glance
- Design roof snow load20 psf
- Ground snow load, ASCE 7 map25 psf
- National rank#665 of 2,758
- Michigan rank#67 of 70
- Population89,168
- Annual snowfall, NOAA normal34.4 in.
- FIPS26087
Lapeer County by the numbers
Nationally that's #665 out of 2,758 rated counties, the top 24%; within Michigan alone, Lapeer County ranks #67 of 70. Michigan counties average 31.7 psf; Lapeer County runs 11.7 psf lower than that.
Lapeer County, FIPS 26087, is home to 89,168 people near 43.0886°N 83.2243°W. Its 25 psf ground snow load figure is the map value; 20 psf is what a roof is actually designed for.
Lapeer County's snowfall, most winters
34.4 in. a year: that's Lapeer County's NOAA 1991-2020 snowfall normal, measured at LAPEER WWTP, MI US (4.6 mi away). See the density guide.
Before you rely on Lapeer County's number
Treat the Lapeer 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.