Wicomico County, MD Roof Snow Load - 20 psf
Wicomico County, MD roof snow load, translated
A typical heated home in Wicomico County is designed to carry 20 pounds per square foot of snow on its roof, per ASCE 7-22. ASCE 7's low-slope-roof minimum (§7.3.4) raises the governing figure to 20 psf - higher than the 14 psf the ground-load formula alone would give, and the code says use the larger one.
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.
Wicomico County at a glance
- Design roof snow load20 psf
- Ground snow load, ASCE 7 map20 psf
- National rank#645 of 2,758
- Maryland rank#12 of 21
- Population106,329
- Annual snowfall, NOAA normal12.8 in.
- FIPS24045
Where Wicomico County ranks
#12 of 21 Maryland counties by design load, top 23% of 2,758 nationally - that's Wicomico County's spot. That's 0.1 psf below Maryland's own county-average design load of 20.1 psf.
FIPS 24045, population 106,329, centered near 38.3674°N 75.6321°W. ASCE 7's underlying ground snow load here is 20 psf before the code's exposure and importance factors bring it to the 20 psf design figure above.
Wicomico County: average annual snowfall
Wicomico County sees about 12.8 in. of snow most winters, per the GREENWOOD 2NE, DE US station's 1991-2020 NOAA normal. Worth noting: the nearest station reporting snowfall normals sits 31.2 mi from Wicomico County's center, so treat this as a regional figure rather than an exact one. See the density guide.
Read this before you use Wicomico 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. Details: the calculation guide.