memo

From: Building Official/David Spencer, CBO

Date: 01/01/2020

Re: Chelan County Structural Loading: Minimum Roof Snow Loads

The purpose of this memo is to implement provisions by establishing the minimum roof snow

load criteria within Chelan County. The minimum roof snow load throughout Chelan County is

40 psf. up to a maximum site elevation of 950 feet above sea level.

Application.

A. For general locations listed in the attached Table 1-C and corresponding map(s) (Chelan

County Roof Snow Loads) loads established are the minimum roof snow load up to the

maximum elevation listed.

B. For areas not listed within Table 1-C the following shall be used when calculating the site

specific snow load:

1) Ground Snow Load. The ground snow load shall be determined in accordance with

the following criteria:

Multiplying the specific site elevation and the given isolines established

in the “Chelan County Chelan County GIS Map.”

Link: https://maps.co.chelan.wa.us/CDGIS/

Find parcel

Click “Contours” tab to display elevation(s)

Click “Snow Load Criteria” tab to display isolines

NOTE: Chelan County defaults to the highest elevation on the parcel and

highest isoline(s) nearest to the parcel

Definitions.

A. Roof Snow Load. “Roof Snow Load” means the weight of snow that is used for the

design of a building or structure.

B. Ground Snow Load. “Ground Snow Load” means the weight of snow on the ground.

40 PSF MIN. ELV. 950 MAX.

40 PSF MIN. ELV. 950 MAX.

40 PSF MIN. ELV. 950 MAX.

40 PSF MIN. ELV. 950 MAX.

40 PSF MIN. ELV. 950 MAX.

55 PSF MIN. ELV. 1100 MAX.

60 PSF MIN. ELV. 960 MAX.

65 PSF MIN. ELV. 1050 MAX.

85 PSF MIN. ELV. 1180 MAX.

120 PSF MIN. ELV. 2000 MAX.

Table 1-C

NOTE: Roof snow loads provided are the minimum

established loads up to, but not greater than, the

maximum elevation(s) provided. Loads shall not be less

than the established minimum(s). Loads greater than the

established minimum(s) & elevation(s) shall be site

specific.

CHELAN COUNTY MIN. ROOF SNOW LOAD(S) 1/1/2020

WENATCHEE (UGA)

ENTIAT (UGA)

CHELAN FALLS

CASHMERE (UGA)

CHELAN (UGA)

MANSON (UGA)

DRYDEN

PESHASTIN (UGA)

LEAVENWORTH (UGA)

CHIWAWA RIVER PINES