# Attaching lid to truss



## Rio (Oct 13, 2009)

I was perusing the Simpson catalog today looking for wall to truss stand off clips; when I was looking at the illustration of how they're attached I saw they use drywall clips that attach to the top plate which makes sense to keep the 1/2" gap from the top of the plate to the bottom of the truss for movement but then I was thinking 'that's okay for where the gyp. board attaches to the plate but out in the field the only place to attach the lid is to the truss so this means that there will be a 1/2" deflection from the wall to the first screw.

It's been awhile since I've hung any drywall but thinking back on it I seem to remember that we attached directly to the bottom chord of the truss and continued that over to the wall intersection. If that's right then the catalog illustration is wrong so I'm thinking I was always doing it wrong. 

My question is........What do the experts have to say on this? Thanks for any insight into this vexing question. I would think that one would see a 1/2" deflection in 16" pretty easily.


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## festerized (May 19, 2007)

Not a big fan of nailing sheetrock directly to trusses 24” OC , 
We run 5/4 x 3 spruce 16” OC


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## Texas Wax (Jan 16, 2012)

Drywall shims


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## Rio (Oct 13, 2009)

festerized said:


> Not a big fan of nailing sheetrock directly to trusses 24” OC ,
> We run 5/4 x 3 spruce 16” OC


That sounds nice, that way we could set the plate with a 5/4 gap, attach to the wall with the DS clip and there would be no out of plane gyp. bd. and it's also nicer being on a 16" schedule than a 24" one although I will say we've done a ton of 24" o.c. lids with no problems being brought to our attention.

There would still be the issue of if the truss did deflect how to design the wall to ceiling drywall to drywall so it wouldn't crack or tear. Any suggestions on how that's done?


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## ubcguy89 (Mar 23, 2013)

Drop the ceiling and frame a Chicago grid ceiling 3" under the trusses. I guarantee the flattest ceiling that will allow got deflection and never crack


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## VinylHanger (Jul 14, 2011)

We have always just attached to the trusses. I think every house I have ever worked on was done the same way. I don't think I can recall ever seeing any cracking at that joint.


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## Golden view (Feb 16, 2012)

VinylHanger said:


> We have always just attached to the trusses. I think every house I have ever worked on was done the same way. I don't think I can recall ever seeing any cracking at that joint.



Me too but I've seen lots and lots of old houses with problems here.


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## Spencer (Jul 6, 2005)

The clip is to combat truss uplift. If you have drywall attached to a nailer on top of an interior partition in the center of the house and this happens you're in trouble.


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## festerized (May 19, 2007)

Spencer said:


> The clip is to combat truss uplift. If you have drywall attached to a nailer on top of an interior partition in the center of the house and this happens you're in trouble.



According to the spec sheet on from Simpson the clip is designed to replace blocking and is not to be used in a structural matter


Sent from my iPhone using Tapatalk


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## Spencer (Jul 6, 2005)

festerized said:


> According to the spec sheet on from Simpson the clip is designed to replace blocking and is not to be used in a structural matter
> 
> 
> Sent from my iPhone using Tapatalk



Right. It's not structural. You're just attaching drywall to it so 18" or so can "float."


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## blacktop (Oct 28, 2012)

If the trusses aren't properly braced . You've got trouble down the road . The clips may help for a short time. But properly bracing the trusses is the key to keep them from walking. [from what I've seen.] Hanging the lids with 5/8 helps too. 2FT On center should be 5/8 . By code nationwide IMO.


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## Rio (Oct 13, 2009)

VinylHanger said:


> We have always just attached to the trusses. I think every house I have ever worked on was done the same way. I don't think I can recall ever seeing any cracking at that joint.


That's the way we've always done it also with never an issue on cracks being brought up. I took a look at the truss calcs and they call out for the drywall to be attached to the truss (see attachment) so it appears that the clips for the drywall that Simpson is calling out for is incorrect for this system. I can understand the rationale for the drywall clips but don't see how they will prevent cracking or tearing at the wall to ceiling intersection if the truss deflects.

If one looks at the truss at this part of the house it's a two point truss so any interior wall will need the stand off clips (not the drywall ones) to keep the wall from potential buckling the truss if the truss deflects which I'm thinking now only occurs under unusual circumstances hence never getting calls from irate clients who are looking at tearing where the wall meets the ceiling. 

To combat truss uplift we call out hurricane clips with the size depending on how much the uplift is calculated to be and those attach at the bearing points of the truss to wall(s).


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## Spencer (Jul 6, 2005)

Rio said:


> That's the way we've always done it also with never an issue on cracks being brought up.
> 
> You are in California. You won't have an issue. Its more of an issue for us that have large swings in seasonal temps like the midwest. The worst truss uplift happens when its extremely cold and the air is very dry. Seems counter intuitive but that's how it works.
> 
> ...


...


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## Big Shoe (Jun 16, 2008)

I'm no help. Not a problem in Florida. :no:


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