Grainger County, TN Roof Snow Load - 10 psf
Grainger County, TN: your roof's ASCE 7 snow number, in plain English
Grainger County's roofs are built to hold 10 psf of snow, the ASCE 7-22 figure a permit reviewer checks first. The physics-based figure alone would be 7 psf, but ASCE 7's own low-slope minimum (§7.3.4) sets a floor of 10 psf for flat and low-pitch roofs here, which is the number that actually governs.
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. A modest addition to standard roof loading. Ordinary residential construction handles this without extra bracing.
Grainger County at a glance
- Design roof snow load10 psf
- Ground snow load, ASCE 7 map10 psf
- National rank#1,880 of 2,758
- Tennessee rank#62 of 95
- Population25,073
- Annual snowfall, NOAA normal3 in.
- FIPS47057
Grainger County by the numbers
Nationally that's #1,880 out of 2,758 rated counties, the top 68%; within Tennessee alone, Grainger County ranks #62 of 95. That's 0.3 psf below Tennessee's own county-average design load of 10.3 psf.
Grainger County, FIPS 47057, is home to 25,073 people near 36.2775°N 83.5095°W. Its 10 psf ground snow load figure is the map value; 10 psf is what a roof is actually designed for.
Grainger County's snowfall, most winters
3 in. a year: that's Grainger County's NOAA 1991-2020 snowfall normal, measured at JEFFERSON CITY, TN US (10.9 mi away). See the density guide.
Before you rely on Grainger County's number
Treat the Grainger 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. See the methodology guide.