Advice and tradesman request for damp chimney stack

[danandpam]

Hi,

We live on Landcroft road in a building that's split between 2 flats. In both flats we're currently we're seeing some small localised damp patches in rooms sharing the chimney stack (see example image attached) that we'd like to get fixed.

We're unsure what skillset is needed to best tackle the problem, and it goes without saying we'd like to approach it in the most efficient (both in effort and cost) way possible.

Any suggestions very welcome.

Many thanks,

Dan

[Salsaboy]

Is the chimney open? Does it have a free flow of air through it? Is it on an outside wall? These are all things that can cause damp patches.

[Herne Hill Guest]

In the photo here you can see where a filling material has been used previously. They most likely did not use a primer before filling and probably used the wrong filler materials. We all, most of us, do this.

[Herne Hill Guest]

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