Originally Posted by kingwood390bh
The vinyl ceiling material will hide most moisture problems.
I agree. Water damage may first appear in an area totally unrelated to the location of the actual leak. Water will enter, then travel along pathways to a pooling point where the swelling will first be noticed.
An edge seam in the luan will absorb water faster than the face of the board (especially if covered in vinyl).
Check for water intruding around the AC and running down to the seam.
Check the roof edge seams near the location of the swelling.
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