I have two patches of damp on my chimney breast upstairs. The chimney is no longer in use. It has been reduced below roof height. It also has a liner insitu. The loft is insulated.
i guess it needs an air flow through the chimney.if the top of the chimney is blocked of and no rain is comming down it then i would check this again.i had the same problem on my chimney breast i put a vent in so that i could get an air flow through this solved the problem.good luck.
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