Douglas County, KS Roof Snow Load - 20 psf
Douglas County, KS roof snow load, translated
A typical heated home in Douglas County is designed to carry 20 pounds per square foot of snow on its roof, per ASCE 7-22. 14 psf is what the ground-load formula alone gives; Douglas 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. A meaningful design load. Most homes built to modern code handle it, but additions, carports, and flat-roofed sections are worth a second look.
Douglas County, KS: quick facts
- Design roof snow load20 psf
- Ground snow load, ASCE 7 map20 psf
- National rank#631 of 2,758
- Kansas rank#4 of 105
- Population121,989
- Annual snowfall, NOAA normal10.4 in.
- FIPS20045
Where Douglas County ranks
#4 of 105 Kansas counties by design load, top 23% of 2,758 nationally - that's Douglas County's spot. Kansas counties average 18.2 psf; Douglas County runs 1.8 psf higher than that.
FIPS 20045, population 121,989, centered near 38.8964°N 95.2909°W. ASCE 7's underlying ground snow load here is 20 psf before the code's exposure and importance factors bring it to the 20 psf design figure above.
Douglas County: average annual snowfall
Douglas County sees about 10.4 in. of snow most winters, per the LAWRENCE, KS US station's 1991-2020 NOAA normal. See the density guide.
Read this before you use Douglas 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.)