Lafayette County, WI Roof Snow Load - 21 psf
Lafayette County, WI: your roof's ASCE 7 snow number, in plain English
Lafayette 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. A meaningful design load. Most homes built to modern code handle it, but additions, carports, and flat-roofed sections are worth a second look.
Lafayette County in numbers
- Design roof snow load21 psf
- Ground snow load, ASCE 7 map30 psf
- National rank#459 of 2,758
- Wisconsin rank#70 of 72
- Population17,306
- Annual snowfall, NOAA normal35.7 in.
- FIPS55065
Lafayette County by the numbers
Nationally that's #459 out of 2,758 rated counties, the top 17%; within Wisconsin alone, Lafayette County ranks #70 of 72. That's 9.9 psf below Wisconsin's own county-average design load of 30.9 psf.
Lafayette County, FIPS 55065, is home to 17,306 people near 42.6556°N 90.1303°W. Its 30 psf ground snow load figure is the map value; 21 psf is what a roof is actually designed for.
Lafayette County's snowfall, most winters
35.7 in. a year: that's Lafayette County's NOAA 1991-2020 snowfall normal, measured at DARLINGTON WWTP, WI US (2 mi away). See the density guide.
Before you rely on Lafayette County's number
Treat the Lafayette 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.