Water damage on gib under wallpaper

miwife, Aug 18, 8:35am
I have moved in to an old rental house and am doing it up for myself. I’m starting with the smallest room in the house (the loo) to see what I could be in for. One wall backs on to the laundry where they seem to have had a broken pipe at some stage. The flooring is marked but solid as a rock. Upon removing old wallpaper with many coats of paint from the loo wall there is a bit of old but dry grey coloured water damage/mould where 2 gib boards meet. Again, it is dry as a bone. About 10cm x 6cm at floor level. Do I need to replace 2 whole sheets of gib or can I seal it and plaster over it? I was wanting to paint over the gib not put more wallpaper on. I don’t want anything coming through the paint. Any suggestions would be appreciated.

zak410, Aug 18, 8:48am
Yes you can seal and plaster over it.
Remember the joints may need too be paper taped before a skim coat and paint, but seal first anyway.

jkp58, Oct 6, 7:56am
wouldn't hurt to put a bit of mold killer on the area .Use oil based sealer over all areas of stripped wall paper other wise you will have trouble with the paste residue