# Seasonal Truss lift, cracks CPS



## rerod (Jan 19, 2009)

I need to refinish the drywall ceiling in my bathroom after patching a small area where a chase was.  It has a truss roof system above it. 24" on center with 1/2" drywall. I need to know the best way to do this.  My plan was to nail new drywall over the existing drywall and start from scratch.  But after reading about CPS I think my method might fail.   Can I install a lid over the old?  Or do I need to take the rock off everything in order to support the lid edges with the wall rock?

Thanks


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## handyguys (Jan 19, 2009)

If the ceiling was installed first, as it should have been, you may just want to try a simple solution first.

When the ceiling rock is installed before the walls then its supported along the edge by the wall rock. In the area where you have truss uplift use a magnet such as
The Handyguys Podcast Amazon Affiliate Store - BUILDER'S MAGNETIC STUD FINDER
and identify all the screws you may have near the edge. i would then remove any screws or nails you have within 18" of the wall. Patch everything up and then paint. 

Worst case is you need to open it up again and do something fancier. Or, did I miss the point of your post?


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## rerod (Jan 19, 2009)

Here's a pic of the rock which will need repaired when the old shower wall (chase) is removed.  Many nailers would be needed and could only be fastened to the trusses to patch where the wall plate was.  I plan on tiling the ceiling in the shower and need 5/8 rock for that anyway (1/2" existing now)so I planned on covering the entire ceiling with 5/8.  Thus my question about wall rock under the lid.  Not next to.

Looks like to do it correctly I would need to remove all rock and start over.  Not screwing the lid closer than 18" to a wall unless its screwed to a nailer attached to the top of the wall plate only.  Do you agree?


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## handyguys (Jan 20, 2009)

I agree with removing the old Sheetrock. I disagree with using 5/8" Sheetrock on the ceiling if you are going to tile. You should use tile backer board, Durock or similar. When tile is done use caulk at the seam between the wall ceiling.


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## rerod (Jan 20, 2009)

16" is the max joist spacing for any cbu product for which I've seen specs.  I would need to add more 'truss' or support somewhere. which would be a good idea for the tile area. 

5/8" rock is what code wants here. And its not a steam shower.


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## glennjanie (Jan 20, 2009)

Hello Rerod:
Your idea of the 5/8" sheetrock is fine, since it is the code in your area. See if you can get it in MR (moisture resistant). Installing the ceiling first, walls next is the accepted method.
Glenn


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