SnowLoadCheck

Johnson County, WY Roof Snow Load - 15 psf

Johnson County, WY: your roof's ASCE 7 snow number, in plain English

Moderate
15 psf

Johnson County's roofs are built to hold 15 psf of snow, the ASCE 7-22 figure a permit reviewer checks first. §7.3.4's low-slope minimum of 15 psf is what actually governs on a flat or low-pitch roof here - higher than the 10.5 psf the base ground-load formula gives.

In depth, not weight: that's roughly 33 inches of fresh, light snow, 12 inches of old, settled snow, or as little as 3 inches of solid ice - snow that heavy is rare here but ice from a freeze-thaw cycle adds up far faster than the depth suggests. 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.

Johnson County in numbers

Johnson County by the numbers

Nationally that's #1,565 out of 2,758 rated counties, the top 57%; within Wyoming alone, Johnson County ranks #15 of 18. Wyoming counties average 17.5 psf; Johnson County runs 2.5 psf lower than that.

Johnson County, FIPS 56019, is home to 8,803 people near 44.044°N 106.5885°W. Its 15 psf ground snow load figure is the map value; 15 psf is what a roof is actually designed for.

Johnson County's snowfall, most winters

35.7 in. a year: that's Johnson County's NOAA 1991-2020 snowfall normal, measured at BILLY CREEK, WY US (9 mi away). See the density guide.

Before you rely on Johnson County's number

Treat the Johnson County figure as a starting point, not a final answer: it assumes standard occupancy, a heated structure and a moderately sheltered site, per ASCE 7-22's own defaults. Exposed terrain, an unheated building or a steeper roof all shift the real number.

For a real application, skip the county number and go straight to the ASCE 7 Hazard Tool - enter your coordinates and it returns a site-specific figure a plan reviewer will recognize. See the methodology guide.