paint on chimneybreast keeps bubbling and peeling
- Thread starter Gary111
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- paint peeling
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It’s an unvented chimney? Then rain is penetrating making it damp which pushes out the salts in the brickwork which pushes off the paint.
Chimney/roof needs checking for leaks and repairing it will then take months for effervescence ( salts leeching out of bricks) to subside after drying .
Chimney/roof needs checking for leaks and repairing it will then take months for effervescence ( salts leeching out of bricks) to subside after drying .
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The damage you see is likely to be quite old , it can take several months for the salts to be washed thru and many more for it to subside. Most likely ingress is at roof/ chimney level , have that checked first . Any exterior photos of that area? What is the property type?
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Gary111,
What responsibility do you have for any repairs outside of your ground floor flat?
1. Why dont you ask the mods to join your posts and put them as one into the Building forum?
2. Read up on similar posts to yours.
3. No water seal or special plaster needed.
4. The rear wall is a solid wall with a lean to - is the air brick you mention inside the lean-to?
5. Is this air brick set into the back wall of the chimney breast?
6. Where exactly is the air brick that you fear is letting rain into the c/breast?
7. The dirty brickwork below the stack is due to the failing stack, and its flaunching allowing moisture into the wall and the flues - damp sooty chemicals have penetrated the wall.
8. The damage to the c/breast in your living room: is caused by hygroscopic chemicals penetrating the walls of the c/breast, & possibly by rising damp - a pic of the front of your c/breast and any hearth would help.
9. Typically, hack off all plaster to 300mm to 500mm above the last signs of damage.
10. Render with a 3:1 mix of sand & lime & limelite skim finish.
11. Replace the skirtings, & the rusted angle beads with plastic angle beads.
12. sweep the flues.
13. Ventilate the flue.
14. For any of this to be successful its necessary to remedy the items at the stack and rear wall.
10. There are a number of other problems beyond & outside your flat - eg concrete levels.
What responsibility do you have for any repairs outside of your ground floor flat?
1. Why dont you ask the mods to join your posts and put them as one into the Building forum?
2. Read up on similar posts to yours.
3. No water seal or special plaster needed.
4. The rear wall is a solid wall with a lean to - is the air brick you mention inside the lean-to?
5. Is this air brick set into the back wall of the chimney breast?
6. Where exactly is the air brick that you fear is letting rain into the c/breast?
7. The dirty brickwork below the stack is due to the failing stack, and its flaunching allowing moisture into the wall and the flues - damp sooty chemicals have penetrated the wall.
8. The damage to the c/breast in your living room: is caused by hygroscopic chemicals penetrating the walls of the c/breast, & possibly by rising damp - a pic of the front of your c/breast and any hearth would help.
9. Typically, hack off all plaster to 300mm to 500mm above the last signs of damage.
10. Render with a 3:1 mix of sand & lime & limelite skim finish.
11. Replace the skirtings, & the rusted angle beads with plastic angle beads.
12. sweep the flues.
13. Ventilate the flue.
14. For any of this to be successful its necessary to remedy the items at the stack and rear wall.
10. There are a number of other problems beyond & outside your flat - eg concrete levels.
Thanks for your very detailed answer, I own the building so am responsible for it.
There are 3 air bricks right at the top of the chimney wall, I am not sure that's causing the problem.
I have had some work on the flaunching some time ago, not sure if it needs doing again without getting someone up there.
The fire places are boarded up, with an air vent behind an electric heater.
I'm not sure if it can be swept now ?
What is failing about the stack please ?
Does it need pointing ?
Is the stack the part that protrudes above the roof ?
What can you see that's wrong with the concrete level please ?
Thanks again.
There are 3 air bricks right at the top of the chimney wall, I am not sure that's causing the problem.
I have had some work on the flaunching some time ago, not sure if it needs doing again without getting someone up there.
The fire places are boarded up, with an air vent behind an electric heater.
I'm not sure if it can be swept now ?
What is failing about the stack please ?
Does it need pointing ?
Is the stack the part that protrudes above the roof ?
What can you see that's wrong with the concrete level please ?
Thanks again.
Perhaps you will answer all the questions I asked above - if not I feel it was a waste of time my asking them?
I cant see the three air bricks - can you point them out on a pic? They, wherever they are, are not the cause of your problems.
Open up all your fireplaces and sweep and smoke test them all.
The stack is the part of the chimney breast that sticks up above the roof.
Your stack at the least needs re-pointing, new flaunching and new lead flashing in place of the mix of lead and mortar fillets it has at the moment.
At best, the stack needs rebuilding.
The blackened brickwork & mortar beds below the stack is degrading.
Concrete levels: do any of your rear rooms have any solid floors? Do you have damp interior lower walls - a pic of the side wall in the yard might help?
I cant see the three air bricks - can you point them out on a pic? They, wherever they are, are not the cause of your problems.
Open up all your fireplaces and sweep and smoke test them all.
The stack is the part of the chimney breast that sticks up above the roof.
Your stack at the least needs re-pointing, new flaunching and new lead flashing in place of the mix of lead and mortar fillets it has at the moment.
At best, the stack needs rebuilding.
The blackened brickwork & mortar beds below the stack is degrading.
Concrete levels: do any of your rear rooms have any solid floors? Do you have damp interior lower walls - a pic of the side wall in the yard might help?
While I think if it there was insulation stuffed in the ground floor one which I removed, may be someone has done the same above.
Also at least one of the fireplaces above has been blocked off with no vent.
Another possibility is that it has no dpc , I can't see one.
Thanks
Also at least one of the fireplaces above has been blocked off with no vent.
Another possibility is that it has no dpc , I can't see one.
Thanks
Have you answered all the questions ? He gets upset you know .
Thanks for that pic of the air bricks - for a proper job you should (you have to) get cracking with work on the stack. Best would be to rebuild it.
I'm corrected, I was searching the lower walls for the a/b's.
The 3 a/b's might possibly
be letting rainwater into the flues but in the scale of things up there they are almost irrelevant.
All flues should end with chimney pots that contain the correct insert terminals appropriate for the flu.
Modern roofing practice is to provide the householder with: before, during and after pics or video of any roof/stack work.
No matter how they are blocked off or sealed, you have to open up all the fireplaces in the building,
all of them, then please post pics of them opened up.
Vents and DPC's are also irrelevant for now.
Do you have a cellar?
I'm corrected, I was searching the lower walls for the a/b's.
The 3 a/b's might possibly
be letting rainwater into the flues but in the scale of things up there they are almost irrelevant.
All flues should end with chimney pots that contain the correct insert terminals appropriate for the flu.
Modern roofing practice is to provide the householder with: before, during and after pics or video of any roof/stack work.
No matter how they are blocked off or sealed, you have to open up all the fireplaces in the building,
all of them, then please post pics of them opened up.
Vents and DPC's are also irrelevant for now.
Do you have a cellar?
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The vents were added when the chimney was capped , probable with flat slabs as can’t see any pots on that side . Chimney capping needs checking.Adding vents internally will help dry any damp .Probably all that’s needed and patience while things dry out and salts stop leeching .
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