SnowLoadCheck

Union County, NJ Roof Snow Load - 20 psf

Union County, NJ: your roof's ASCE 7 snow number, in plain English

Moderate
20 psf

Union County's roofs are built to hold 20 psf of snow, the ASCE 7-22 figure a permit reviewer checks first. 17.5 psf is what the ground-load formula alone gives; Union 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. Modern-code homes carry a load like this without issue; an older addition, a carport, or any flat-roofed section is where it is worth checking first.

Union County at a glance

Union County by the numbers

Nationally that's #532 out of 2,758 rated counties, the top 19%; within New Jersey alone, Union County ranks #9 of 17. That's 0.1 psf below New Jersey's own county-average design load of 20.1 psf.

Union County, FIPS 34039, is home to 594,160 people near 40.6599°N 74.3087°W. Its 25 psf ground snow load figure is the map value; 20 psf is what a roof is actually designed for.

Union County's snowfall, most winters

21.4 in. a year: that's Union County's NOAA 1991-2020 snowfall normal, measured at PLAINFIELD, NJ US (6.3 mi away). See the density guide.

Before you rely on Union County's number

Treat the Union 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. (How this figure is calculated.)