# Is it necessary to attach tongue and groove ceiling board ends to joists?



## dropkick (Nov 20, 2020)

I'm not sure if this is the right forum or if the question makes sense. What I mean is should I position the end of each board on a joist when installing tongue and groove ceiling?

It seems to be standard practice but I don't think it's necessary because of the interlocking. As long the board ends are not in the same place on each row of board, the interlocking should prevent the end from bending.

I ask because I'm using a very hard wood (Ipe) that requires screws rather than finish nails. I'm not confident that 3/4" space under the joist at the end of a board can handle a screw without cracking…even predrilled. It also seems a little wasteful to cut the boards so the end lands exactly on a joist.

Just wondering if anyone has much experience with tongue and ceilings and have they tried not attaching the board ends to joists?


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## WoodenDreams (Aug 23, 2018)

10 yrs ago I installed 1/4"x3"x96" tongue and groove - bead boards onto the ceiling. I used 3/4" brad nails to secure it up to the joists. The area that ended next to the walls did not have joists. I could have at this time added 2×2 strips to the joists to secure the ends, but didn't need to. I used trim molding on the walls at the ceiling after the ceiling was installed for esthetics. The trim hide any gaps where the boards met the wall. Still up and secure. I did cut a couple ceiling trap doors into the ceiling, for access to the heat/AC ductwork for ductwork cleaning.


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## rwe2156 (May 7, 2014)

I think you should.


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## craftsman on the lake (Dec 27, 2008)

Practice is staggered seams and on joists. But, in the long run it might be fine not to.


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## bold1 (May 5, 2013)

Unless you're not spanning more then 2' and as long as you have joist to joist pieces on either side of your end splice you should be fine. Any farther than 2' and I'd suggest a floating cat across the 2 side pieces and the end splice.


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## Nubsnstubs (Aug 30, 2013)

One of my customers has a house that's 40 years old this year. Some of the ceilings in the house are 2×6 T&G. Some of the boards were just butted in between joists. 
Forty years later, some of the boards have no support because of shrinkage. The 2×6's shrank to where you can see a gap on each edge of the board. For the last 6-7 years, I've been securing the pieces when it looks to be an issue. The joists are on 48" centers.

My thoughts are to never butt 2 pieces of wood together unless there is some kind of support no matter how little span there is…....... ............. Jerry (in Tucson)


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## SMP (Aug 29, 2018)

Ipe does tend to crack/split at the ends. I personally wouldn't bother with T&G boards. Joists should be 24" on center where you are? And overlap means each end will be adjacent to a board that is attached about a foot from the end?


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## pottz (Sep 15, 2015)

ipe is a very hard dense wood and if it is t&g you should have no problem.i agree it's very expensive so why waste wood if not needed.on a deck you can span 2-3 foot and have no flex standing on it so for a ceiling i dont think it's an issue.as far as splits and cracking on the ends i wouldn't worry about it,just use some end seal and you should be fine.


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