Winneshiek County, IA Roof Snow Load - 24.5 psf
Winneshiek County, IA: your roof's ASCE 7 snow number, in plain English
Winneshiek County's roofs are built to hold 24.5 psf of snow, the ASCE 7-22 figure a permit reviewer checks first.
In depth, not weight: that's roughly 53.9 inches of fresh, light snow, 19.6 inches of old, settled snow, or as little as 4.9 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.
Winneshiek County in numbers
- Design roof snow load24.5 psf
- Ground snow load, ASCE 7 map35 psf
- National rank#340 of 2,758
- Iowa rank#14 of 99
- Population19,723
- Annual snowfall, NOAA normal37.5 in.
- FIPS19191
Winneshiek County by the numbers
Nationally that's #340 out of 2,758 rated counties, the top 12%; within Iowa alone, Winneshiek County ranks #14 of 99. Iowa counties average 21.7 psf; Winneshiek County runs 2.8 psf higher than that.
Winneshiek County, FIPS 19191, is home to 19,723 people near 43.293°N 91.8508°W. Its 35 psf ground snow load figure is the map value; 24.5 psf is what a roof is actually designed for.
Winneshiek County's snowfall, most winters
37.5 in. a year: that's Winneshiek County's NOAA 1991-2020 snowfall normal, measured at DECORAH, IA US (2.9 mi away). See the density guide.
Before you rely on Winneshiek County's number
Treat the Winneshiek 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.