Design Criteria


Effective date: Oct. 1, 2022 with a 6-month phase-in period.
Phase-in period ends: March 31, 2023
*During the phase-in period use of the 2019 OSSC or the 2022 OSSC is permitted
View the permanent rules.

Current Codes in Effect

Design Criteria for Prescriptive Residential Structures

  • Seismic: Design Category D
  • Wind Exposure:
    • Basic Wind Speed: 97 miles per hour (mph)    
    • Coastal Special Wind Region: 97 mph
    • Structures With Direct Exposure to the Pacific Ocean: 135 mph                                                                                         
  • Roof Snow Load: 25 per square foot (psf) - The design roof snow load may not be less than 20 psf with no rain-on-snow surcharge as applicable.
  • Ground Snow Load: 36 psf - For site specific ground snow loads, refer to the online lookup tool or the online map published by the Structural Engineers Association of Oregon (SEAO).
  • Frost Depth: 18 inches
  • Soil Load-Bearing Values: 1,500 psf
  • Exposure Category: C
  • Weather Classification: Moderate

Engineered Structural Design Criteria

  • Reference Chapter 16 of the Oregon Structural Specialty Code for full design criteria parameters.
  • Reference Chapter 18 for Soils and Foundations values
  • For Site specific design parameters use the online tool provided by The Applied Technology Council (ATC).