Howard County, IA Roof Snow Load - 28 psf
Howard County, IA: your roof's ASCE 7 snow number, in plain English
Howard County's roofs are built to hold 28 psf of snow, the ASCE 7-22 figure a permit reviewer checks first.
In depth, not weight: that's roughly 61.6 inches of fresh, light snow, 22.4 inches of old, settled snow, or as little as 5.6 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. Modern-code homes carry a load like this without issue; an older addition, a carport, or any flat-roofed section is where it is worth checking first.
Howard County in numbers
- Design roof snow load28 psf
- Ground snow load, ASCE 7 map40 psf
- National rank#266 of 2,758
- Iowa rank#6 of 99
- Population9,360
- Annual snowfall, NOAA normal40.3 in.
- FIPS19089
Howard County by the numbers
Nationally that's #266 out of 2,758 rated counties, the top 10%; within Iowa alone, Howard County ranks #6 of 99. 21.7 psf is Iowa's typical county figure - Howard County beats it by 6.3 psf.
Howard County, FIPS 19089, is home to 9,360 people near 43.3653°N 92.3219°W. Its 40 psf ground snow load figure is the map value; 28 psf is what a roof is actually designed for.
Howard County's snowfall, most winters
40.3 in. a year: that's Howard County's NOAA 1991-2020 snowfall normal, measured at CRESCO 1 NE, IA US (11.6 mi away). See the density guide.
Before you rely on Howard County's number
Treat the Howard 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. (How this figure is calculated.)