This might be a bit boring, but if you've got a few minutes to spare you might be able to throw some light onto my damp ceiling mystery! This all concerns a late-1950s bungalow:
I have a strange problem with the ceiling around an old boiler chimney in the kitchen, which has been playing its silly joke on me for twelve and a half years now. I'm curious to know if this is typical of a known problem or if - as is the case with nearly every problem I ever encounter - I'm the only person in the history of mankind to experience this.
The situation is that ever since we have been here, there has been a damp patch on the ceiling in two rooms, centred on a boiler chimney in the kitchen, where it goes up through the ceiling (this chimney is built onto a dividing wall between the kitchen and sitting room, so the ceiling in both rooms is affected). The diameter of the damp patch is about three feet, complete with nice tide mark in the ceiling paintwork.
In the loft the back of the plasterboard is damp to the extent that the backing can be picked off by fingernail like wet tissue paper. It has been like this for the twelve and a half years we've been here and there is evidence of it being like it for a considerable time beforehand.
The obvious suspect would be the chimney leaking, but there was no evidence of dampness or leaks around the chimney immediately inside the roof. Nevertheless, when we swapped over to a combi boiler and got rid of the oil-fired heating we had the chimney taken down to just inside the loft. That was about seven years ago and the ceiling is still as damp today as it was twelve years ago.
Another suspect was the various plumbed pipes that run nearby, but for a good couple of years I've had plastic sheeting and tissue paper test areas laid out between the pipes and the back of the ceiling below, and they have remained dry the whole time. So, it's not the pipes, nor the roof.
I have also taken down the rest of the chimney inside the loft down to ceiling level and the brickwork was dry all the way down to the damp ceiling level.
The only other thing I could think of was if the chimney was acting as a wick and drawing moisture from the ground, right up to the ceiling. The only problem with that theory is that there appears to be no damp in the chimney at all below about two feet under the ceiling, and the lower chimney appears to be dry (the chimney design is like a pedestal, so it's only full width from about four feet upwards, with the bottom four feet being a much thinner 'pedestal' column of bricks).
So, it appears that the dampness is occurring in the ceiling around the chimney, but the source is neither above or below it, nor related to leaking pipework, which of course is absurd.
The wall in the sitting room has at some point lost part of its plaster (before we got here!), obviously due to this damp problem and was boarded over, so it suggests that the problem has been present for a very long time.
I intend to remove the rest of the chimney down to ground level, and of course remove the damp parts of the ceiling to re-board and plaster it, along with boarding and plastering the sitting room wall, but I really want to solve this mystery so I can make sure that all my work doesn't get ruined by the dampness remaining/returning.
Have any of you come across this kind of problem before? The only thing I can think of was the aforementioned wick effect, but as also mentioned, there is no sign of dampness from the ground level up to within a couple of feet of the ceiling.
Thanks for reading.
Mike
I have a strange problem with the ceiling around an old boiler chimney in the kitchen, which has been playing its silly joke on me for twelve and a half years now. I'm curious to know if this is typical of a known problem or if - as is the case with nearly every problem I ever encounter - I'm the only person in the history of mankind to experience this.
The situation is that ever since we have been here, there has been a damp patch on the ceiling in two rooms, centred on a boiler chimney in the kitchen, where it goes up through the ceiling (this chimney is built onto a dividing wall between the kitchen and sitting room, so the ceiling in both rooms is affected). The diameter of the damp patch is about three feet, complete with nice tide mark in the ceiling paintwork.
In the loft the back of the plasterboard is damp to the extent that the backing can be picked off by fingernail like wet tissue paper. It has been like this for the twelve and a half years we've been here and there is evidence of it being like it for a considerable time beforehand.
The obvious suspect would be the chimney leaking, but there was no evidence of dampness or leaks around the chimney immediately inside the roof. Nevertheless, when we swapped over to a combi boiler and got rid of the oil-fired heating we had the chimney taken down to just inside the loft. That was about seven years ago and the ceiling is still as damp today as it was twelve years ago.
Another suspect was the various plumbed pipes that run nearby, but for a good couple of years I've had plastic sheeting and tissue paper test areas laid out between the pipes and the back of the ceiling below, and they have remained dry the whole time. So, it's not the pipes, nor the roof.
I have also taken down the rest of the chimney inside the loft down to ceiling level and the brickwork was dry all the way down to the damp ceiling level.
The only other thing I could think of was if the chimney was acting as a wick and drawing moisture from the ground, right up to the ceiling. The only problem with that theory is that there appears to be no damp in the chimney at all below about two feet under the ceiling, and the lower chimney appears to be dry (the chimney design is like a pedestal, so it's only full width from about four feet upwards, with the bottom four feet being a much thinner 'pedestal' column of bricks).
So, it appears that the dampness is occurring in the ceiling around the chimney, but the source is neither above or below it, nor related to leaking pipework, which of course is absurd.
The wall in the sitting room has at some point lost part of its plaster (before we got here!), obviously due to this damp problem and was boarded over, so it suggests that the problem has been present for a very long time.
I intend to remove the rest of the chimney down to ground level, and of course remove the damp parts of the ceiling to re-board and plaster it, along with boarding and plastering the sitting room wall, but I really want to solve this mystery so I can make sure that all my work doesn't get ruined by the dampness remaining/returning.
Have any of you come across this kind of problem before? The only thing I can think of was the aforementioned wick effect, but as also mentioned, there is no sign of dampness from the ground level up to within a couple of feet of the ceiling.
Thanks for reading.
Mike
