McCook County, SD Roof Snow Load - 28 psf
McCook County, SD roof snow load, translated
A typical heated home in McCook County is designed to carry 28 pounds per square foot of snow on its roof, per ASCE 7-22.
On a roof that means 61.6 in. of fresh snow, 22.4 in. once it packs down, or 5.6 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.
Already snow on the roof in McCook County?
McCook County at a glance
- Design roof snow load28 psf
- Ground snow load, ASCE 7 map40 psf
- National rank#276 of 2,758
- South Dakota rank#32 of 65
- Population5,771
- Annual snowfall, NOAA normal31 in.
- FIPS46087
Where McCook County ranks
#32 of 65 South Dakota counties by design load, top 10% of 2,758 nationally - that's McCook County's spot. That's 0.2 psf below South Dakota's own county-average design load of 28.2 psf.
FIPS 46087, population 5,771, centered near 43.6804°N 97.358°W. ASCE 7's underlying ground snow load here is 40 psf before the code's exposure and importance factors bring it to the 28 psf design figure above.
McCook County: average annual snowfall
McCook County sees about 31 in. of snow most winters, per the MONTROSE, SD US station's 1991-2020 NOAA normal. See the density guide.
Read this before you use McCook 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.