San Mateo County, CA Roof Snow Load - 0 psf
San Mateo County, CA roof snow load, translated
A typical heated home in San Mateo County is designed to carry 0 pounds per square foot of snow on its roof, per ASCE 7-22.
On a roof that means 0 in. of fresh snow, 0 in. once it packs down, or 0 in. of solid ice - three very different piles for the same load. Snow load is not a factor in roof design here at all; the ground snow load figure maps to zero.
Snow on San Mateo County's roofs right now?
San Mateo County at a glance
- Design roof snow load0 psf
- Ground snow load, ASCE 7 map0 psf
- National rank#2,501 of 2,758
- California rank#19 of 41
- Population742,893
- Annual snowfall, NOAA normal0 in.
- FIPS06081
Where San Mateo County ranks
#19 of 41 California counties by design load, top 91% of 2,758 nationally - that's San Mateo County's spot. That's 1.1 psf below California's own county-average design load of 1.1 psf.
FIPS 06081, population 742,893, centered near 37.4147°N 122.3715°W. ASCE 7's underlying ground snow load here is 0 psf before the code's exposure and importance factors bring it to the 0 psf design figure above.
San Mateo County: average annual snowfall
San Mateo County sees about 0 in. of snow most winters, per the HALF MOON BAY, CA US station's 1991-2020 NOAA normal. See the density guide.
Read this before you use San Mateo County's figure
The figure above assumes the case ASCE 7-22 treats as typical: a heated, ordinary-occupancy home on a partially exposed site. Change any of those - exposure, heating, roof pitch, occupancy category - and the real design number moves.
A building permit needs the number at your exact address, not the county average - the free ASCE 7 Hazard Tool returns that from your coordinates in about a minute and produces a PDF a plan reviewer will accept. (How this figure is calculated.)