Green County, WI Roof Snow Load - 21 psf
Green County, WI: your roof's ASCE 7 snow number, in plain English
Green County's roofs are built to hold 21 psf of snow, the ASCE 7-22 figure a permit reviewer checks first.
In depth, not weight: that's roughly 46.2 inches of fresh, light snow, 16.8 inches of old, settled snow, or as little as 4.2 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.
Green County, WI: quick facts
- Design roof snow load21 psf
- Ground snow load, ASCE 7 map30 psf
- National rank#445 of 2,758
- Wisconsin rank#68 of 72
- Population37,183
- Annual snowfall, NOAA normal31.2 in.
- FIPS55045
Green County by the numbers
Nationally that's #445 out of 2,758 rated counties, the top 16%; within Wisconsin alone, Green County ranks #68 of 72. 30.9 psf is Wisconsin's typical county figure - Green County comes in 9.9 psf under it.
Green County, FIPS 55045, is home to 37,183 people near 42.6755°N 89.6051°W. Its 30 psf ground snow load figure is the map value; 21 psf is what a roof is actually designed for.
Green County's snowfall, most winters
31.2 in. a year: that's Green County's NOAA 1991-2020 snowfall normal, measured at BLANCHARDVILLE #2, WI US (16.1 mi away). See the density guide.
Before you rely on Green County's number
Treat the Green 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. Details: the calculation guide.