SnowLoadCheck

Arlington County, VA Roof Snow Load - 20 psf

Arlington County, VA roof snow load, translated

Moderate
20 psf

A typical heated home in Arlington County is designed to carry 20 pounds per square foot of snow on its roof, per ASCE 7-22. 17.5 psf is what the ground-load formula alone gives; Arlington County's 20 psf low-slope minimum (§7.3.4) beats it, so that figure is the one that governs on flat and low-pitch roofs.

On a roof that means 44 in. of fresh snow, 16 in. once it packs down, or 4 in. of solid ice - three very different piles for the same load. Modern-code homes carry a load like this without issue; an older addition, a carport, or any flat-roofed section is where it is worth checking first.

Arlington County in numbers

Where Arlington County ranks

#16 of 110 Virginia counties by design load, top 21% of 2,758 nationally - that's Arlington County's spot. That's 1.7 psf above Virginia's own county-average design load of 18.3 psf.

FIPS 51013, population 239,807, centered near 38.8783°N 77.1007°W. ASCE 7's underlying ground snow load here is 25 psf before the code's exposure and importance factors bring it to the 20 psf design figure above.

Arlington County: average annual snowfall

Arlington County sees about 13.4 in. of snow most winters, per the FRANCONIA 1.3 SSE, VA US station's 1991-2020 NOAA normal. See the density guide.

Read this before you use Arlington County's figure

The figure above assumes the case ASCE 7-22 treats as typical: a heated, ordinary-occupancy home on a partially exposed site. Change any of those - exposure, heating, roof pitch, occupancy category - and the real design number moves.

A building permit needs the number at your exact address, not the county average - the free ASCE 7 Hazard Tool returns that from your coordinates in about a minute and produces a PDF a plan reviewer will accept. (How this figure is calculated.)