dot and dab problems

[stebed]

I am having problems with a dot and dab plaster board wall that is in the kitchen of a house i am preparing for sale. The dots are showing through the plaster and the primer and now the paint. They look like a damp stain but damp stain cover doesn't cover them. The wall is dry as plastering was done months after it was dry walled and the plaster was painted months after the plastering was done. This is the only area in the whole house where this has happened so it is not a problem with the plaster or dry wall adhesive.

Has anyone had this and if so what sort of undercoat was used to cure it?

Many Thanks

 

[jbonding]

this usually appears on cellars or cold walls, maybe a rad on this wall or batton, insulate, over board and skim for quicker results if your selling

 

[stebed]

Well it is an exterior wall but the only solution for it will be a primer as it is in the kitchen with base units already so the fixes you mention are imposable. I will go and ask at my local painting supplies shop I guess.