Worcester County, MD Roof Snow Load - 20 psf
Worcester County, MD roof snow load, translated
A typical heated home in Worcester County is designed to carry 20 pounds per square foot of snow on its roof, per ASCE 7-22. The physics-based figure alone would be 14 psf, but ASCE 7's own low-slope minimum (§7.3.4) sets a floor of 20 psf for flat and low-pitch roofs here, which is the number that actually governs.
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. This is a meaningful design load - most modern-code homes handle it fine, though an addition, a carport or a flat-roofed section can be a weak spot.
Worcester County, MD: quick facts
- Design roof snow load20 psf
- Ground snow load, ASCE 7 map20 psf
- National rank#724 of 2,758
- Maryland rank#15 of 21
- Population54,337
- Annual snowfall, NOAA normal12.8 in.
- FIPS24047
Where Worcester County ranks
#15 of 21 Maryland counties by design load, top 26% of 2,758 nationally - that's Worcester County's spot. That's 0.1 psf below Maryland's own county-average design load of 20.1 psf.
FIPS 24047, population 54,337, centered near 38.2221°N 75.3099°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.
Worcester County: average annual snowfall
Worcester County sees about 12.8 in. of snow most winters, per the GREENWOOD 2NE, DE US station's 1991-2020 NOAA normal. That station is far enough away (43.5 mi) that local snowfall - especially at a different elevation or near a lake - can run noticeably higher or lower than this figure. See the density guide.
Read this before you use Worcester 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.)