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RE: Wood truss deflection space

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WTCA has developed a Truss Technology for Builders brochure called
"partition separation." This shows 4 floating corner details that when used
seem to eliminate any downstream problems. At least we have yet to see a
site that used them that had a problem. Call Michele McCormick at our office
at 608-274-4849, ext. 26 to get a single copy of this document. Any further
questions please ask us.

Kirk Grundahl
Executive Director WTCA

-----Original Message-----
From: Greg Smith [mailto:strusup(--nospam--at)]
Sent: Sunday, August 08, 1999 4:15 PM
To: seaint(--nospam--at)
Subject: Re: Wood truss deflection space

     It is the obvious solution and therefore probably not  the reasonable
solution that you are looking for but the only way I can think to solve it
is to use boards (size up to you) perpendicular to the plane of the trusses
and joining the trusses. Having short nailers between the boards/beams and
all dropped down to the top of wall height.
Best if panel points are at multiples of 4' of course.

-----Original Message-----
From: Jeff Smith <smthengr(--nospam--at)>
To: seaint(--nospam--at) <seaint(--nospam--at)>
Date: Saturday, August 07, 1999 7:47 PM
Subject: Wood truss deflection space

>I am working on a (under)funded housing project with 32 foot wood trusses
>that have a midspan DL deflection of .11" and about .25" TL deflection. The
>lower chords have a segmented "camber" of 1/8" per 10 feet so that the
>trusses do not bear on interior walls. Simpson makes truss clips that allow
>for deflection and a connection of the truss over non-bearing walls as well
>as ceiling sheetrock clips. The sheetrock clips are intended to be
>such that the ceiling sheetrock is not nailed to the bottom of the truss
>within 16" of the non-bearing wall, so the sheetrock actually bends
>to the top of the wall plates. Needless to say the drywallers are not
>enamored with this detail. The drywallers want to install the sheetrock to
>the bottom of the truss at interior walls. My question concerns the
>deflection detail for the ceiling sheetrock. We are looking at maybe
>.14-.16" of LL midspan deflection for a 32 foot span. Are the any
>alternatives to avoiding the ceiling sheetrock deflection detail. I know
>that this detail is many times ignored, yet others are steadfast in
>declaring its importance.
>Jeff Smith