Sierra County, CA Roof Snow Load - Case Study Area
Why doesn't Sierra County have a snow load number?
Sierra County sits in the mountain-west terrain where ASCE 7-22 §7.2 itself declines to give a contour figure - elevation changes too fast over short distances there for one number per county to mean anything. The code requires a site-specific study for a building here, not a look-up.
Sierra County, FIPS 06091, is home to 3,113 people - one of 386 US counties ASCE 7 itself routes around a map figure for.
Sierra County, CA: quick facts
- Population3,113
- Annual snowfall, NOAA normal37.8 in.
- FIPS06091
Typical snowfall in Sierra County, CA
NOAA's 30-year normal for Sierra County: 37.8 in. of snow a year, from the PORTOLA, CA US station. (fresh vs. packed vs. ice explains why.)
What this Sierra 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.
Sierra 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.