The map below is a resource for engineers designing structures for wind loads in Seattle.  It shows wind exposure and terrain adjustment factors, was derived from the wind load provisions in ASCE 7-02, and is appropriate for those using ASCE 7 or SEAW’s Rapid Solutions Manual in their designs.

The color-coded areas identify wind speed-up areas in Seattle, with acceptable Kzt values and areas defined as being Exposure Category C. The Kzt values will be accepted by DPD as default values for Kzt in lieu of the calculated values required by Section 6.5.7.2 of ASCE 7-02.  Similarly the areas identified as Exposure Category C will be accepted by DPD in lieu of a determination required by Section 6.5.6.3 of ASCE 7-02.  NOTE:  There are no areas in Seattle that DPD requires to be considered as Exposure Category D.

Instructions Click on a numbered section of the map to view that area in greater detail.  The detailed maps require Adobe Acrobat Reader to view (download free software).  Use Acrobat's zoom tools, located on the toolbar, to control the level of detail.