i have had these damp spots appear in my single brick extension it has been dot and dabed and it was not silver backed plasterboard but it is coming through an internal brick wall, external walls where battened with no problems, where the damp is coming through half way up the wall its coming through on the dab but only on some dab only 2 places and there must be 12 dot and dabbed aeras on the wall, thats why i cant tell how its get damp halfway up the wall and only in 1 place just asking out of curiosity its been like this for a year not getting any worse!
