Rockingham County, NH Roof Snow Load - 35 psf
Rockingham County, NH: your roof's ASCE 7 snow number, in plain English
Rockingham County's roofs are built to hold 35 psf of snow, the ASCE 7-22 figure a permit reviewer checks first.
In depth, not weight: that's roughly 77 inches of fresh, light snow, 28 inches of old, settled snow, or as little as 7 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 load this size is a serious structural matter; pre-modern-code homes and low-slope or flat-roofed sections are the ones most worth an inspection.
Rockingham County, NH: quick facts
- Design roof snow load35 psf
- Ground snow load, ASCE 7 map50 psf
- National rank#94 of 2,758
- New Hampshire rank#4 of 4
- Population322,433
- Annual snowfall, NOAA normal62.6 in.
- FIPS33015
Rockingham County by the numbers
Nationally that's #94 out of 2,758 rated counties, the top 3%; within New Hampshire alone, Rockingham County ranks #4 of 4. That's 15.8 psf below New Hampshire's own county-average design load of 50.8 psf.
Rockingham County, FIPS 33015, is home to 322,433 people near 42.9887°N 71.0991°W. Its 50 psf ground snow load figure is the map value; 35 psf is what a roof is actually designed for.
Rockingham County's snowfall, most winters
62.6 in. a year: that's Rockingham County's NOAA 1991-2020 snowfall normal, measured at N HAMPTON, NH US (14.1 mi away). See the density guide.
Before you rely on Rockingham County's number
Treat the Rockingham 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.