Dorchester County, MD Roof Snow Load - 20 psf
What ASCE 7 says about snow load in Dorchester County
That's Dorchester County's design roof snow load per ASCE 7-22, for a typical heated single-family home - the number a permit reviewer starts from. Flat and low-pitch roofs in Dorchester County are actually governed by ASCE 7's §7.3.4 minimum of 20 psf, not the 14 psf the ground-load formula alone would produce.
Converted to something you can actually eyeball on a roof: about 44 in. of fresh powder, 16 in. once it settles and packs down, or just 4 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.
Dorchester County at a glance
- Design roof snow load20 psf
- Ground snow load, ASCE 7 map20 psf
- National rank#840 of 2,758
- Maryland rank#19 of 21
- Population33,138
- Annual snowfall, NOAA normal12.8 in.
- FIPS24019
Where Dorchester County's figure sits nationally
Out of 2,758 rated US counties, Dorchester County sits at #840, the top 30% nationally - #19 of 21 within Maryland. That's 0.1 psf below Maryland's own county-average design load of 20.1 psf.
Near 38.4292°N 76.0474°W, FIPS 24019: Dorchester County counts 33,138 residents and a 20 psf map value, which the code's own factors turn into 20 psf.
How much it actually snows in Dorchester County
Most winters bring Dorchester County roughly 12.8 in. of snow - NOAA's normal at GREENWOOD 2NE, DE US, 36.9 mi off. 36.9 mi is a real gap between Dorchester County and its nearest reporting station, so local snowfall can diverge from this figure, especially near elevation changes. (fresh vs. packed vs. ice explains why.)
Read this before you rely on it
Dorchester 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 Dorchester County's county-wide figure. Details: the calculation guide.