Livingston County, MI Roof Snow Load - 20 psf
Livingston County, MI: your roof's ASCE 7 snow number, in plain English
Livingston 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 17.5 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.
Livingston County, MI: quick facts
- Design roof snow load20 psf
- Ground snow load, ASCE 7 map25 psf
- National rank#587 of 2,758
- Michigan rank#61 of 70
- Population196,976
- Annual snowfall, NOAA normal33.2 in.
- FIPS26093
Livingston County by the numbers
Nationally that's #587 out of 2,758 rated counties, the top 21%; within Michigan alone, Livingston County ranks #61 of 70. That's 11.7 psf below Michigan's own county-average design load of 31.7 psf.
Livingston County, FIPS 26093, is home to 196,976 people near 42.6025°N 83.9117°W. Its 25 psf ground snow load figure is the map value; 20 psf is what a roof is actually designed for.
Livingston County's snowfall, most winters
33.2 in. a year: that's Livingston County's NOAA 1991-2020 snowfall normal, measured at HOWELL WWTP, MI US (1.2 mi away). See the density guide.
Before you rely on Livingston County's number
Treat the Livingston 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.