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RE: MBR Tie-Down System

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You are correct that even holdowns that anchor floor to floor will loosen 
from shrinkage because floor joists will experience much more shrinkage 
than the vertical stud portion because of wood grain direction.

I agree that TJM products shrink less than sawn lumber, but depending on 
the environment, swelling will occur between when the TJM's are produced 
and when it makes it to the job site (especially stored outside in a moist 
environment!).  So over time, shrinkage will occur and holdowns will surely 
loosen again.

From: 	T[SMTP:vicpeng(--nospam--at)]
Reply To: 	seaoc(--nospam--at)
Sent: 	Monday, March 16, 1998 1:54 PM
To: 	seaoc(--nospam--at)
Subject: 	Re: MBR Tie-Down System

Hope this works!

Subject: RE: MBR Tie-Down System

>I've seen a building in the Seattle area which is a five story condominium 
>that suffered extensive exterior wall water intrusion because of some
>flashing and sealing issues around the windows.  When the General
>Contractor opened up some shear walls, he found the holdowns were loose.
> The threaded rods were pretty much sloppy in the stud bays.

The problem occurs even if you anchor floor by floor.  I have usually 
specified that the anchors be tightened regularly during construction (I 
never specifiy full buildng height anchor rods because of shrinkage) with a 
final turn and nut-locking immediately before closure.  By that time (often 
a number of months) I estimate less than 1% remaining shrinkage.  Over the 
depth of a floor (10" +/-) I figure the amount of slack will be minimal? 
 With TJM products there is almost no shrinkage.

Thor Tandy