Fulton County, IL Roof Snow Load - 20 psf
Fulton County, IL: your roof's ASCE 7 snow number, in plain English
Fulton County's roofs are built to hold 20 psf of snow, the ASCE 7-22 figure a permit reviewer checks first. 14 psf is what the ground-load formula alone gives; Fulton 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.
Got real snow on a Fulton County roof right now?
Fulton County at a glance
- Design roof snow load20 psf
- Ground snow load, ASCE 7 map20 psf
- National rank#848 of 2,758
- Illinois rank#42 of 102
- Population32,510
- Annual snowfall, NOAA normal14.4 in.
- FIPS17057
Fulton County by the numbers
Nationally that's #848 out of 2,758 rated counties, the top 31%; within Illinois alone, Fulton County ranks #42 of 102. Illinois counties average 19.3 psf; Fulton County runs 0.7 psf higher than that.
Fulton County, FIPS 17057, is home to 32,510 people near 40.4652°N 90.2023°W. Its 20 psf ground snow load figure is the map value; 20 psf is what a roof is actually designed for.
Fulton County's snowfall, most winters
14.4 in. a year: that's Fulton County's NOAA 1991-2020 snowfall normal, measured at CANTON, IL US (9.8 mi away). See the density guide.
Before you rely on Fulton County's number
Treat the Fulton 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.