Smith County, MS Roof Snow Load - 5 psf
Smith County, MS: your roof's ASCE 7 snow number, in plain English
Smith County's roofs are built to hold 5 psf of snow, the ASCE 7-22 figure a permit reviewer checks first. Flat and low-pitch roofs in Smith County are actually governed by ASCE 7's §7.3.4 minimum of 5 psf, not the 3.5 psf the ground-load formula alone would produce.
In depth, not weight: that's roughly 11 inches of fresh, light snow, 4 inches of old, settled snow, or as little as 1 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. Standard residential construction handles a load this size without extra bracing; it is a modest addition on top of ordinary roof loading.
Smith County at a glance
- Design roof snow load5 psf
- Ground snow load, ASCE 7 map5 psf
- National rank#2,347 of 2,758
- Mississippi rank#62 of 82
- Population14,051
- Annual snowfall, NOAA normal0.9 in.
- FIPS28129
Smith County by the numbers
Nationally that's #2,347 out of 2,758 rated counties, the top 85%; within Mississippi alone, Smith County ranks #62 of 82. 6.5 psf is Mississippi's typical county figure - Smith County comes in 1.5 psf under it.
Smith County, FIPS 28129, is home to 14,051 people near 32.019°N 89.4949°W. Its 5 psf ground snow load figure is the map value; 5 psf is what a roof is actually designed for.
Smith County's snowfall, most winters
0.9 in. a year: that's Smith County's NOAA 1991-2020 snowfall normal, measured at RALEIGH 6N, MS US (9.2 mi away). See the density guide.
Before you rely on Smith County's number
Treat the Smith 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.