infiniteMPG wrote:
We're looking at putting up a tongue and groove ceiling in our kitchen
to match the T&G we just finished in the porch (the kitchen opens into
the porch) and we had a quick question. When we put the T&G up should
we put it directly against the joists, should be use something like
tar roofing paper first to seal the ceiling, or should we put it over
sheetrock?
....

Interior there's really nothing to seal against--that's what the roof is
for. If it's an attic above, the use of a barrier simply to stop any
possible dust infiltration would be wise but that really would be its
only function.

As for whether to use another layer, the key is how even the joists
are--if they are close, directly to them is fine; otherwise you'll
either want to shim or use furring strips to be able to even out the
high/low spots. Of course, the joists need to be running perpendicular
to the direction you want to run the ceiling or you'll need the furring
strips to have a nailing surface the other direction.

I don't see any point in the sheetrock other than it could be the dust
barrier spoken of athough it adds weight and is much more work to hang
for to be simply covered up. And it surely wouldn't serve any purpose I
can see to even tape it at all if did...

Well, I guess there might be one facet of sheetrock as a fire retardant
barrier between floors, perhaps...

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