Sitka's Structural Design Criteria

(For use with the International Building Code 2009 or the American Society of Civil Engineers - Minimum Design Loads for Buildings and Other Structures ASCE 7-05.)

  • Wind Load:
    Basic wind speed, V (3-second gust wind speed) = 120 miles per hour
  • Snow Load:
    Ground snow load, pg = 50 pounds per square foot
  • Earthquake Load:
    Maximum considered earthquake ground motion-
    0.2 second spectral response, Ss = 0.97 g
    1.0 second spectral response, S1 = 0.50 g
  • Frost Depth:
    Minimum of 18 inches required from finish grade to base of footing or base of non-frost susceptible fill.
  • Wind Exposure Definitions

Codes in effect in Sitka:

Residential (set by Sitka General Code):

  • 2009 International Residential Code

Commercial (set by State regulation)

  • 2009 International Building, Fire, and Mechanical Codes
  • 2012 Uniform Plumbing Code
  • 2014 National Electric Code