Washington County, NE Roof Snow Load - 20 psf
Washington County, NE roof snow load, translated
A typical heated home in Washington County is designed to carry 20 pounds per square foot of snow on its roof, per ASCE 7-22. The physics-based figure alone would be 17.5 psf, but ASCE 7's own low-slope minimum (§7.3.4) sets a floor of 20 psf for flat and low-pitch roofs here, which is the number that actually governs.
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.
Washington County, NE: quick facts
- Design roof snow load20 psf
- Ground snow load, ASCE 7 map25 psf
- National rank#943 of 2,758
- Nebraska rank#29 of 93
- Population21,254
- Annual snowfall, NOAA normal34.4 in.
- FIPS31177
Where Washington County ranks
#29 of 93 Nebraska counties by design load, top 34% of 2,758 nationally - that's Washington County's spot. 20.2 psf is Nebraska's typical county figure - Washington County comes in 0.2 psf under it.
FIPS 31177, population 21,254, centered near 41.534°N 96.2246°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.
Washington County: average annual snowfall
Washington County sees about 34.4 in. of snow most winters, per the BENNINGTON 3WSW, NE US station's 1991-2020 NOAA normal. See the density guide.
Read this before you use Washington 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.