Allen County, OH Roof Snow Load - 20 psf
Allen County, OH: your roof's ASCE 7 snow number, in plain English
Allen 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; Allen 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. A meaningful design load. Most homes built to modern code handle it, but additions, carports, and flat-roofed sections are worth a second look.
Allen County at a glance
- Design roof snow load20 psf
- Ground snow load, ASCE 7 map20 psf
- National rank#652 of 2,758
- Ohio rank#25 of 86
- Population100,866
- Annual snowfall, NOAA normal18.5 in.
- FIPS39003
Allen County by the numbers
Nationally that's #652 out of 2,758 rated counties, the top 24%; within Ohio alone, Allen County ranks #25 of 86. Allen County's figure lands almost exactly on Ohio's own county-average of 20 psf.
Allen County, FIPS 39003, is home to 100,866 people near 40.7716°N 84.1061°W. Its 20 psf ground snow load figure is the map value; 20 psf is what a roof is actually designed for.
Allen County's snowfall, most winters
18.5 in. a year: that's Allen County's NOAA 1991-2020 snowfall normal, measured at LIMA WWTP, OH US (3.5 mi away). See the density guide.
Before you rely on Allen County's number
Treat the Allen 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.