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RE: builders win big in first code hearing round

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My interest in the code change comes from a different angle.  Currently in Seattle the city uses a wind map that was developed based on the simplified method of the IBC.  It paints broad areas of the city and surroundings with wind speed up factors of 1.38 to 2.0.  Unfortuantely much of those areas don't meet ASCE7 criteria for wind speed up to start with (H/L_sub_h < 0.2) amongst other problems with the map.  The more frustrating part is that you can almost be guaranteed a plans review comment on any design because the reviewers simply punch in an address and the system generates a wind speed/exposure and speed up factor for the address.  We are constantly having to argue the case for none or lower wind speedup effects base on actual site topography. 
I don't think that topographic effects should be ignored but the city's adoption of the wind map is a problem and frankly we're not finding any bodies.

Dan Morrow, PE
Seattle, WA 98121


From: Rhkratzse(--nospam--at) [mailto:Rhkratzse(--nospam--at)]
Sent: Tuesday, October 17, 2006 1:38 PM
To: Dan Morrow; seaint(--nospam--at)
Subject: Re: builders win big in first code hearing round

In a message dated 10/17/06 12:44:27 PM, dmorrow(--nospam--at) writes:
The approved language significantly limits the application of wind speed-up effect requirements to local jurisdictions where there are documented, historical records of damage ...

Sort of like, we have to have a death at *EACH* intersection before we'll consider adding stop signs or traffic lights, right?  Mere intellectual evaluation of the situation, extrapolating from similar conditions elsewhere, won't do?  In other words *I* have to get lung cancer before I'll consider quitting.


Ralph Hueston Kratz
Structural Engineer
Richmond CA USA