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RE: Truss gap over the wall

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Simpson has an HTC heavy truss clip that has published loads for up to 1 1/4" gap between the truss and the top plate.
-------------- Original message --------------
From: "Bill Allen" <T.W.Allen(--nospam--at)>



According to the Simpson catalog (see footnote), the gap is limited to ¼? in order to achieve the published loads. I wish Simpson would update these devices so that they are consistent with the truss recommendations of ½? gap.


Don?t ask me what I do. The Simpson DTC clip is still about the only thing I know that works. Even though I?ve specified these in the past, don?t develop a lot of confidence that this detail will be achieved just because you?ve got it on your drawings.


IMO, the best way to achieve the desired intent is to require that the perpendicular partitions are made of metal stud and are connected at the top via a slip track connection. Someone else mentioned using a slip track connection on a wood stud wall. I?m not sure how this would be detailed, but the concept is good.


I?m not sure if I?ve been clear in conveying that I?m not convinced specifying DTC clips will achieve the intended results.




T. William (Bill) Allen, S.E.


Consulting Structural Engineers
V (949) 248-8588 ? F(949) 209-2509

-----Original Message-----
From: Chance, Acie [mailto:AChance(--nospam--at)]
Sent: Monday, March 06, 2006 3:35 PM
Subject: RE: Truss gap over the wall


Thanks to Christopher, John, Jason, Ray, Rodger and Harold.  I believe the Simpson Clips with the DS gypsum wallboard supports will work.  I sure hope the thousands of homes like mine which have the interior walls nailed to the bottom truss chords do not fall down any time soon.  It is not good to have been a carpenter before being an engineer.



Thanks again

Acie Chance

-----Original Message-----
From: Raymond Shreenan [mailto:rshreenan(--nospam--at)]
Sent: Monday, March 06, 2006 3:15 PM
To: seaint(--nospam--at)
Subject: Truss gap over the wall



One of the reasons not to allow the truss to bear on the interior wall is that it was most likely designed to clear span from exterior wall to exterior wall or girder truss.  If you give it bearing interior it causes stress reversals and changes in the loads to the members which may be greater than the original dedign results.  At the same time the wall has to be supported at the top.  The Simpson truss clips are slotted to allow vertical deflection of the truss without loading the wall and provides lateral support of the wall perpendicular to the truss.  

Ray Shreenan SE