Oglala Lakota County, SD Roof Snow Load - 20 psf
How much snow is too much for a roof in Oglala Lakota County, SD?
20 psf: that's what ASCE 7-22 requires a typical heated home's roof in Oglala Lakota County to carry. §7.3.4's low-slope minimum of 20 psf is what actually governs on a flat or low-pitch roof here - higher than the 14 psf the base ground-load formula gives.
Picture it, not just weigh it: 44 in. if it's fresh powder, 16 in. once it settles, or a mere 4 in. if it's 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.
Oglala Lakota County at a glance
- Design roof snow load20 psf
- Ground snow load, ASCE 7 map20 psf
- National rank#1,057 of 2,758
- South Dakota rank#60 of 65
- Population13,360
- Annual snowfall, NOAA normal43.8 in.
- FIPS46102
How Oglala Lakota County compares
20 psf ranks #1,057 of 2,758 US counties with a mapped snow load (top 38%) - and #60 of 65 in South Dakota. That's 8.2 psf below South Dakota's own county-average design load of 28.2 psf.
Population 13,360 (FIPS 46102), roughly 43.3334°N 102.5615°W. The 20 psf ground snow load ASCE 7-22 maps here becomes 20 psf once the code's own design factors are applied.
Typical snowfall in Oglala Lakota County, SD
NOAA's 30-year normal for Oglala Lakota County: 43.8 in. of snow a year, from the OELRICHS, SD US station. That station is far enough away (35.5 mi) that local snowfall - especially at a different elevation or near a lake - can run noticeably higher or lower than this figure. (fresh vs. packed vs. ice explains why.)
What this Oglala Lakota County figure assumes
This is a county-level reference figure for a typical heated home built to Risk Category II (ordinary residential), on a partially exposed lot - the assumptions ASCE 7-22 itself treats as the default case. A steeper roof, a fully exposed hilltop lot, an unheated structure, or a higher risk category all change the actual number.
Oglala Lakota County's permit office wants an address-specific figure, not this county average - the ASCE 7 Hazard Tool is free, takes under a minute, and outputs a PDF most reviewers accept. Details: the calculation guide.