Could this damp be from the flashing around chimney?

Am I missing something or should there be a lead flashing where the tile hanging meets the chimney?
 
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If you have timber framing, there will be at least 50 mm of mineral wool between the external flue and the outer side of the timber frame. This is there for 2 reasons - to accommodate differential movement between the masonry and the timber frame, and as a fire barrier. This movement, over the 50-odd years, winter and summer, that the house has stood, has probably settled the vertical insulation leaving a small gap at the top where it originally met the insulation in the roof space, creating a cold bridge.

In turn this cold corner at ceiling level meets humid warm air and condensation occurs, creating damp in the plasterboard at upper level. It is a continuous cycle that occurs each autumn to spring, then dries during the summer.

Thus the 7-odd mild damp patches and the three-year history of poor paint adhesion in the same area of your daughter's bedroom, could possibly remedied by a simple rearrangement and possibly addition of insulation in the roof space.

It is so unlikely to be salts or a leak considering the internalization of the timber frame structure, there would be other more damaging indications of water ingress.

Another problem to look out for in the roof is condensation on the underside of the membrane, which may be dripping onto the surface of the roofspace insulation.

I'd get a roof insulation specialist, or two, to do you a free survey in case there are grants available to upgrade your 1960s insulation, assuming it hasn't been done already.
 
Removing your chimney stack removes a traditional design feature from the building.

If you in future want the gifts of a solid fuel fire then re-building a stack costs far more than dropping it.

If the stack goes you will still need to have the remaining flue swept, and ventilated high and low.
 
Thanks to everyone who has provided their expertise its very much appreciated

Just an update, the patches are still there on the wall but it hasnt rained for a few days now and what is more puzzling is that if it was water ingress from the chimney would there be new patches of damp on the wall? At present nothing has changed since I posted the first picture?

The loftspace above has been insulated in the past 3 years by BG, the only thing I can think of if this is the case is that in the loft the insulation does not go right up to the eaves as there needs to be ventilation from the soffits.

Flyboytim how can it be remedied by a simple rearrangement?
 
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OK, so the space is accessible then - could the extent and coverage of the insulation in the area near the damp spots be investigated, at least with a handheld camera or a mirror and light source?

Is the plasterboard (ceiling and wall junction) exposed and can the various insulation materials - wall and loft - be moved to cover any exposed areas? Does this then prevent free flow of air over rafters?

What sort of roofing felt do you have?

Can you provide photos?

Don't BG guarantee their work? Could you ask them to come back and sort it, perhaps?

Practical suggestion, if you have a desk fan, point it in the general direction of the damp patches, to help them evaporate and to warm that corner between wall and ceiling to the same as room temperature. What happens?

Warmer weather is coming, the damp will disappear by itself if condensation is the cause.
 
Hi

I dont think so.

What is strange though is that its been dry for the past 10 days and yet the damp patches are still there?
 

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