Houghton County, MI Roof Snow Load - 49 psf

How much snow is too much for a roof in Houghton County, MI?

Picture it, not just weigh it: 107.8 in. if it's fresh powder, 39.2 in. once it settles, or a mere 9.8 in. if it's ice. A serious structural load. Homes built before modern snow-load provisions, or with low-slope/flat roof sections, are the ones most worth having checked.

Houghton County in numbers

• Design roof snow load49 psf
• Ground snow load, ASCE 7 map70 psf
• National rank#14 of 2,758
• Michigan rank#3 of 70
• Population38,041
• Annual snowfall, NOAA normal177.7 in.
• FIPS26061

How Houghton County compares

49 psf ranks #14 of 2,758 US counties with a mapped snow load (top 1%) - and #3 of 70 in Michigan. That's 17.3 psf above Michigan's own county-average design load of 31.7 psf.

Population 38,041 (FIPS 26061), roughly 46.9984°N 88.6519°W. The 70 psf ground snow load ASCE 7-22 maps here becomes 49 psf once the code's own design factors are applied.

Typical snowfall in Houghton County, MI

NOAA's 30-year normal for Houghton County: 177.7 in. of snow a year, from the ONTONAGON 6 SE, MI US station. Worth noting: the nearest station reporting snowfall normals sits 28.6 mi from Houghton County's center, so treat this as a regional figure rather than an exact one. (fresh vs. packed vs. ice explains why.)

What this Houghton County figure assumes

This is a county-level reference figure for a typical heated home built to Risk Category II (ordinary residential), on a partially exposed lot - the assumptions ASCE 7-22 itself treats as the default case. A steeper roof, a fully exposed hilltop lot, an unheated structure, or a higher risk category all change the actual number.

Houghton County's permit office wants an address-specific figure, not this county average - the ASCE 7 Hazard Tool is free, takes under a minute, and outputs a PDF most reviewers accept. Details: the calculation guide.