SnowLoadCheck

Durham County, NC Roof Snow Load - 15 psf

What ASCE 7 says about snow load in Durham County

Moderate
15 psf

That's Durham County's design roof snow load per ASCE 7-22, for a typical heated single-family home - the number a permit reviewer starts from. §7.3.4's low-slope minimum of 15 psf is what actually governs on a flat or low-pitch roof here - higher than the 10.5 psf the base ground-load formula gives.

Converted to something you can actually eyeball on a roof: about 33 in. of fresh powder, 12 in. once it settles and packs down, or just 3 in. if it's turned to ice. 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.

Durham County, NC: quick facts

Where Durham County's figure sits nationally

Out of 2,758 rated US counties, Durham County sits at #1,314, the top 48% nationally - #12 of 100 within North Carolina. That's 2.1 psf above North Carolina's own county-average design load of 12.9 psf.

Near 36.0338°N 78.8781°W, FIPS 37063: Durham County counts 343,628 residents and a 15 psf map value, which the code's own factors turn into 15 psf.

How much it actually snows in Durham County

Most winters bring Durham County roughly 1.7 in. of snow - NOAA's normal at BUTNER FLTR PLT, NC US, 9.5 mi off. (fresh vs. packed vs. ice explains why.)

Read this before you rely on it

Durham County's number above is ASCE 7-22's default case, not a custom calculation: ordinary residential occupancy, heated, sited on ground that's neither fully sheltered nor fully exposed. Any one of those changing - pitch, exposure, heating, occupancy - moves the real figure.

Nothing here substitutes for an address-level number. Get one free, in about a minute, from the ASCE 7 Hazard Tool using your own coordinates rather than Durham County's county-wide figure. Details: the calculation guide.