Pictures? Brand? Model? Type? How it was installed? Anything to help us help you....................

I have used it before on projects. Porch ceilings are one of the best places to use it, nobody touches it.

As long as it is installed correctly, to account for the expansion and contraction, then it's fine. All materials will expand and contract more outside in uncontrolled environments.

Sure, but why? Wood is a lovely, forgiving, renewable material. No reason to use plastic in that lodation.

wood may be renewable, but it is expensive to replace plaster board, then paint and it will have to be painted again. Beadboard will not have to be pained will it? We have peeling paint which is of course inattractive.

I think that is what is on my porch ceiling. Been here 18 years, and it was there when I bought the house. I painted it haint blue.