Mellette County, SD Roof Snow Load - 21 psf
Mellette County, SD roof snow load, translated
A typical heated home in Mellette County is designed to carry 21 pounds per square foot of snow on its roof, per ASCE 7-22.
On a roof that means 46.2 in. of fresh snow, 16.8 in. once it packs down, or 4.2 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.
Mellette County in numbers
- Design roof snow load21 psf
- Ground snow load, ASCE 7 map30 psf
- National rank#486 of 2,758
- South Dakota rank#56 of 65
- Population1,834
- Annual snowfall, NOAA normal40 in.
- FIPS46095
Where Mellette County ranks
#56 of 65 South Dakota counties by design load, top 18% of 2,758 nationally - that's Mellette County's spot. South Dakota counties average 28.2 psf; Mellette County runs 7.2 psf lower than that.
FIPS 46095, population 1,834, centered near 43.5813°N 100.7552°W. ASCE 7's underlying ground snow load here is 30 psf before the code's exposure and importance factors bring it to the 21 psf design figure above.
Mellette County: average annual snowfall
Mellette County sees about 40 in. of snow most winters, per the CEDAR BUTTE, SD US station's 1991-2020 NOAA normal. See the density guide.
Read this before you use Mellette 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.)