Chimney breast damp

[Bethan Saunders]

Hi. First time posting and hoping I can get some help or advice.

February 2020 I noticed a small damp patch coming from the top of my bedroom wall. The wall is the chimney breast.

Round the houses, a few people told me my chimney was the cause, so took it down in May 2020 as I no longer had a fire.

Winter came and the wet patch grew some more. So assumed the chimney hadn't been taken down correctly and water was still getting in.

Fast forward to now and a roofer has been to see the problem, however no water in the attic. No light coming through so he's of the opinion. The chimney removal was done correctly... However can't explain the patch in the bedroom which has grown again this winter.

Ive read a few places this could a hygroscopic salt problem.

So firstly how or who would i get to test this theory?
Secondly, how fixable is it, should it turn out to be that.

Photos attached showing the growth of the patch

 

[JohnD]

is that an external wall, or a chimneybreast? What is on the other side of that wall?

are there any pipes or tanks in the loft?

it does not look like salts to me, nor condensation. It looks like a leak.

draw round it with a pencil, write the date on the line, photograph it frequently and see if it changes with weather or something else.

Are the flues chimney ventilated at the bottom, with an airbrick or similar where each fireplace used to be?

Is there a steamy bathroom?

 

[tell80]

Are you saying the whole chimney breast and the chimney stack on the roof have been removed?

For Hygroscopic saltss
Where the chimney breast in the bedroom has been removed,
was the back wall thoroughly cleaned of all soot stains?
With the back wall its best to clean spotless and then blind with two coats of SBR.
Next its good to use two coats of sand and lime render but dont use any gypsum plaster.

Having said that it doesnt look like a Hygroscopic salts stain?
You need to go in the loft and examine the wall/roof just above the stain.
You also need pics of conditions on the roof and any remaining stack.

 

[Bethan Saunders]

Hi, An update.
No trademans believes salts to be the issue, so that is something out of the equation.
Removing the paint revealed the plaster is actually ok, and not damaged. however, while the patch hasn't grown anymore in the previous 3 months, it still looks "wetter" once we get a deluge of rain.
My plasterer right now believes these is a leak. however the attic still shows no water or light coming in, so I assume that would mean no water could be getting in. (however being a girl who has no clue with DIY I may be wrong there).
Im totally at a loss on how this can be fixed and don't want to be painting the room (this wall is planned for plastering as I've created a stud wall to extend it) and have another patch show up in a few months time.

is that an external wall, or a chimneybreast? What is on the other side of that wall?

are there any pipes or tanks in the loft?

it does not look like salts to me, nor condensation. It looks like a leak.

draw round it with a pencil, write the date on the line, photograph it frequently and see if it changes with weather or something else.

Are the flues chimney ventilated at the bottom, with an airbrick or similar where each fireplace used to be?

Is there a steamy bathroom?

The wall is internal, and connected to my neighbour. who also had a damp patch, but not as large as mine. Hers has not dried out either, however not grown also.
No trademan that has been up the attic mentioned pipes, but I do know there is pipes in that corner from my old combi boiler. they are currently behind the wardrobes so I assume they go into the attic.
As mentioned, no growth, just looking more wet when we have rain,
There is no vents, the guy that took my stack down said I didn't need anything as I no longer had the gas fire, just an electric one which is never used.

Are you saying the whole chimney breast and the chimney stack on the roof have been removed?

For Hygroscopic saltss
Where the chimney breast in the bedroom has been removed,
was the back wall thoroughly cleaned of all soot stains?
With the back wall its best to clean spotless and then blind with two coats of SBR.
Next its good to use two coats of sand and lime render but dont use any gypsum plaster.

Having said that it doesnt look like a Hygroscopic salts stain?
You need to go in the loft and examine the wall/roof just above the stain.
You also need pics of conditions on the roof and any remaining stack.

Im waiting for a 4th roofer to get back to me to go up and have a look, my father (carpenter by trade so not a roofer but has built many a house over the years and works for Taylor Wimpey currently as Site manager) reckons it looks ok where the stack was removed.

 

[tell80]

Do you feel comfortable going up into the roof space because it would be a good start for you to go up there & take pics of the party wall, and the roof where the stack used to go up?

Has the stack above the roof been completely removed?
Is any of the chimney breast remaining in the loft space?
Was your chimney breast back to back with your neighbour's chimney breast, & did you both share a stack?

 

[Nige F]

Or get a selfie stick and poke that up through the traphatch - unless you have a proper built in loft ladder. And boarding to walk on in the loft