Construction Codes

What codes does Olympia enforce?

The City of Olympia enforces the following National Codes, Washington State Amendments, and the Olympia Municipal Code:

National codes

Washington State amendments

Washington State Amendments 

Local amendments and regulations

City of Olympia design requirements 

  • Engineering Design and Development Standards (EDDS)
  • Wind Speed Maps:
    • Risk Category I IBC Figure 1609.3(3)
    • Risk Category II IBC Figure 1609.3(1)
    • Risk Category III & IV IBC Figure 1609.3(2)
  • Roof Snow Load: 25 psf 
  • Rain on Snow Surcharge: 5 psf added to low-slope roofs if slope is for carport (roof slope <1/2") otherwise, rain on snow surcharge: 5 psf added to flat roofs if slope is <1/2"  (IBC 1608.1 & ASCE 7-10)
  • Seismic Design Category: D IBC 1613
  • Rainfall: 1 inches/hour for roof drainage design
  • Frost Line Depth: 12 inches
  • Soil Baring Capacity: 1,500 psf unless a Geo-Technical report is provided


Interpretation Policies


Contact the Permit Center at 360.753.8314 or

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