Washington County, AR Roof Snow Load - 10 psf
Washington County, AR: your roof's ASCE 7 snow number, in plain English
Washington County's roofs are built to hold 10 psf of snow, the ASCE 7-22 figure a permit reviewer checks first. 7 psf is what the ground-load formula alone gives; Washington County's 10 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 22 inches of fresh, light snow, 8 inches of old, settled snow, or as little as 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 modest add-on to standard roof loading - ordinary residential construction carries it without extra bracing.
Washington County at a glance
- Design roof snow load10 psf
- Ground snow load, ASCE 7 map10 psf
- National rank#1,672 of 2,758
- Arkansas rank#8 of 75
- Population266,184
- Annual snowfall, NOAA normal5.5 in.
- FIPS05143
Washington County by the numbers
Nationally that's #1,672 out of 2,758 rated counties, the top 61%; within Arkansas alone, Washington County ranks #8 of 75. That's 0.1 psf below Arkansas's own county-average design load of 10.1 psf.
Washington County, FIPS 05143, is home to 266,184 people near 35.978°N 94.2173°W. Its 10 psf ground snow load figure is the map value; 10 psf is what a roof is actually designed for.
Washington County's snowfall, most winters
5.5 in. a year: that's Washington County's NOAA 1991-2020 snowfall normal, measured at ODELL 2 N, AR US (17.6 mi away). See the density guide.
Before you rely on Washington County's number
Treat the Washington 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.