Clackamas County, OR Roof Snow Load - Case Study Area
Why doesn't Clackamas County have a snow load number?
ASCE 7's own snow load map has no single figure for Clackamas County: the terrain is complex enough that the code (§7.2) requires an elevation-specific study rather than a county-wide value. That is the map being accurate, not a data gap.
FIPS 41005, population 425,857. 386 US counties get this same case-study treatment; Clackamas County is one of them.
Clackamas County in numbers
- Population425,857
- Annual snowfall, NOAA normal5 in.
- FIPS41005
Clackamas County's snowfall, most winters
5 in. a year: that's Clackamas County's NOAA 1991-2020 snowfall normal, measured at THREE LYNX, OR US (6.7 mi away). See the density guide.
Before you rely on Clackamas County's number
Treat the Clackamas 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. See the methodology guide.