Smith County, KS Roof Snow Load - 20 psf
Smith County, KS roof snow load, translated
A typical heated home in Smith County is designed to carry 20 pounds per square foot of snow on its roof, per ASCE 7-22. 17.5 psf is what the ground-load formula alone gives; Smith County's 20 psf low-slope minimum (§7.3.4) beats it, so that figure is the one that governs on flat and low-pitch roofs.
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.
Snow on Smith County's roofs right now?
Smith County, KS: quick facts
- Design roof snow load20 psf
- Ground snow load, ASCE 7 map25 psf
- National rank#1,242 of 2,758
- Kansas rank#51 of 105
- Population3,541
- Annual snowfall, NOAA normal22.6 in.
- FIPS20183
Where Smith County ranks
#51 of 105 Kansas counties by design load, top 45% of 2,758 nationally - that's Smith County's spot. 18.2 psf is Kansas's typical county figure - Smith County beats it by 1.8 psf.
FIPS 20183, population 3,541, centered near 39.7847°N 98.7854°W. ASCE 7's underlying ground snow load here is 25 psf before the code's exposure and importance factors bring it to the 20 psf design figure above.
Smith County: average annual snowfall
Smith County sees about 22.6 in. of snow most winters, per the LEBANON, KS US station's 1991-2020 NOAA normal. See the density guide.
Read this before you use Smith 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. See the methodology guide.