SnowLoadCheck

Knox County, IN Roof Snow Load - 20 psf

Knox County, IN: your roof's ASCE 7 snow number, in plain English

Moderate
20 psf

Knox County's roofs are built to hold 20 psf of snow, the ASCE 7-22 figure a permit reviewer checks first. 14 psf is what the ground-load formula alone gives; Knox 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.

In depth, not weight: that's roughly 44 inches of fresh, light snow, 16 inches of old, settled snow, or as little as 4 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.

Knox County at a glance

Knox County by the numbers

Nationally that's #809 out of 2,758 rated counties, the top 29%; within Indiana alone, Knox County ranks #35 of 89. That's 0.7 psf above Indiana's own county-average design load of 19.3 psf.

Knox County, FIPS 18083, is home to 35,872 people near 38.6884°N 87.4204°W. Its 20 psf ground snow load figure is the map value; 20 psf is what a roof is actually designed for.

Knox County's snowfall, most winters

8.5 in. a year: that's Knox County's NOAA 1991-2020 snowfall normal, measured at VINCENNES 5 NE, IN US (5 mi away). See the density guide.

Before you rely on Knox County's number

Treat the Knox 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. Details: the calculation guide.