When I was going to gypsum the ceiling in a former laundry room, I discovered that the pipe penetration in the ceiling where a dryer was mounted was not sealed and warm/moist air has leaked into the ceiling, causing approximately 1m2 around the penetration to rot. (The room is on the second floor and the pipe goes through the ceiling->Attic->outer roof.)
My plan was to do as follows (but I am open to tips.)
Remove the pipe penetration, saw away the damaged part, and nail on new boards.
Then frame up and install gypsum.
The question is whether I need to install some form of vapor barrier or something between the gypsum and the board ceiling? There was paper on the ceiling before, but it was removed when I tore it down.
The house is from 1926
/B
