Washington County, OH Roof Snow Load - 20 psf
Washington County, OH: your roof's ASCE 7 snow number, in plain English
Washington County's roofs are built to hold 20 psf of snow, the ASCE 7-22 figure a permit reviewer checks first. Flat and low-pitch roofs in Washington County are actually governed by ASCE 7's §7.3.4 minimum of 20 psf, not the 14 psf the ground-load formula alone would produce.
In depth, not weight: that's roughly 44 inches of fresh, light snow, 16 inches of old, settled snow, or as little as 4 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.
Washington County, OH: quick facts
- Design roof snow load20 psf
- Ground snow load, ASCE 7 map20 psf
- National rank#710 of 2,758
- Ohio rank#42 of 86
- Population58,332
- Annual snowfall, NOAA normal21.7 in.
- FIPS39167
Washington County by the numbers
Nationally that's #710 out of 2,758 rated counties, the top 26%; within Ohio alone, Washington County ranks #42 of 86. Washington County's figure lands almost exactly on Ohio's own county-average of 20 psf.
Washington County, FIPS 39167, is home to 58,332 people near 39.4507°N 81.4906°W. Its 20 psf ground snow load figure is the map value; 20 psf is what a roof is actually designed for.
Washington County's snowfall, most winters
21.7 in. a year: that's Washington County's NOAA 1991-2020 snowfall normal, measured at MARIETTA LOCK 1, OH US (3.4 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.