Alexandria city, VA Roof Snow Load - 20 psf
Alexandria city, VA: your roof's ASCE 7 snow number, in plain English
Alexandria city'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 Alexandria city are actually governed by ASCE 7's §7.3.4 minimum of 20 psf, not the 17.5 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. A meaningful design load. Most homes built to modern code handle it, but additions, carports, and flat-roofed sections are worth a second look.
Alexandria city in numbers
- Design roof snow load20 psf
- Ground snow load, ASCE 7 map25 psf
- National rank#615 of 2,758
- Virginia rank#19 of 110
- Population159,102
- Annual snowfall, NOAA normal13.4 in.
- FIPS51510
Alexandria city by the numbers
Nationally that's #615 out of 2,758 rated counties, the top 22%; within Virginia alone, Alexandria city ranks #19 of 110. Virginia counties average 18.3 psf; Alexandria city runs 1.7 psf higher than that.
Alexandria city, FIPS 51510, is home to 159,102 people near 38.8193°N 77.0837°W. Its 25 psf ground snow load figure is the map value; 20 psf is what a roof is actually designed for.
Alexandria city's snowfall, most winters
13.4 in. a year: that's Alexandria city's NOAA 1991-2020 snowfall normal, measured at FRANCONIA 1.3 SSE, VA US (5.9 mi away). See the density guide.
Before you rely on Alexandria city's number
Treat the Alexandria city 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.)