SnowLoadCheck

Williamson County, TN Roof Snow Load - 10 psf

Williamson County, TN: your roof's ASCE 7 snow number, in plain English

Light
10 psf

Williamson 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; Williamson 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.

Williamson County, TN: quick facts

Williamson County by the numbers

Nationally that's #1,670 out of 2,758 rated counties, the top 61%; within Tennessee alone, Williamson County ranks #11 of 95. 10.3 psf is Tennessee's typical county figure - Williamson County comes in 0.3 psf under it.

Williamson County, FIPS 47187, is home to 269,136 people near 35.8948°N 86.8979°W. Its 10 psf ground snow load figure is the map value; 10 psf is what a roof is actually designed for.

Williamson County's snowfall, most winters

1.7 in. a year: that's Williamson County's NOAA 1991-2020 snowfall normal, measured at FRANKLIN SEWAGE PLT, TN US (3.6 mi away). See the density guide.

Before you rely on Williamson County's number

Treat the Williamson 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.)