Damp on chimney breast - any ideas?

R.O.S.S.I

R.O.S.S.I

R.O.S.S.I

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Hi all, noticed yesterday that a damp patch has formed in our main bedroom at the top of the chimney breast and i'm just wondering if anyone may be able to offer any advice/guidance on sussing out what has caused it and subsequently fixing it so it doesn't continue.

Here is a pic of the offending area...

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I haven't noticed it so it leads me to believe that its formed over the past few weeks or so and the only change I can think of that I made was to shove a chimney balloon up the open fireplace downstairs a few weeks back in an effort to stop the draft from coming down and heat from flying up the chimney.

I'm thinking that it could just be a result of the chimney balloon being there so i've taken it out for now and will see how I get on and I'm going to borrow a dehumidifier and run it for a couple of days just to see if it gets any better.

If it turns out to not have been the chimney balloon causing it, what else could be the likely source of it? We sleep with the window open at night so there is minimal, if any, condensation inside the windows when we wake up in the morning and have the heating on in the house most evenings.

The chimney was swept before we moved in and is just an open fireplace in the lounge below (waiting for a log burner to go in).

The wall that is showing is the chimney breast in a traditional semi, so behind that is next doors chimney breast etc, it isn't an outside/exposed wall.
 
There is a chance the balloon has contributed somewhat as airflow through will help the chimney stay dry inside.

Most likely, as mentioned already, its failing flashing, probably on the uproof side of the chimney.
 
Not something that I can easily get onto the roof and check myself really, bummer.

I've not been up into the loft yet but am I likely to see water coming in somewhere in the loft space?

Anyone any rough ideas of how much something like that is likely to cost me to get sorted?
 
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R.O.S.S.I said:
Not something that I can easily get onto the roof and check myself really, bummer.

I've not been up into the loft yet but am I likely to see water coming in somewhere in the loft space?

Anyone any rough ideas of how much something like that is likely to cost me to get sorted?
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Give a roofer a ring, they'll go up and check it out for free and give you a quote for the work. I wouldn't leave it long as it will cause more damage over time.
 
R.O.S.S.I said:
Anyone any rough ideas of how much something like that is likely to cost me to get sorted?
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depends greatly on what needs doing, but we had the rear chimney gully flashing replaced for about £500 on an old property - thats Surrey pricing and it was pretty hard to access so could probably be done cheaper
 
Will try and get some guys out over next couple of days. The absolute hammering of rains we've had around the North West recently will no doubt be what has exacerbated the issue!

Really hoping this doesn't unearth some other jobs that need doing or he "finds" work to do.
 
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Had one guy up this morning. This guy said it isn't the flashing its the flaunching around the chimney pots at the top and that the pointing needs doing on the chimney stack too.

Luckily my next door neighbour caught him whilst he was up there and neighbour has agreed to get his side done and go halves on it as he is having some other work done on his extension too.

He said he'll "reflaunch" it (if that's a word haha), get rid of the chimney pots not required and replace with vents, repoint the chimney stack and clear the gutters for £275.

Not too unreasonable I don't think but I'm going to see what the other two chaps say needs doing first!
 
I had this issue just recently on my house, my damp was a lot worse however.

The problem is likely to be the same in that the flashings (lead skirting on chimney) have probably worn on the chimney and as a result water is getting in, albeit a small amount.

There are two ways to fix this and I was quoted the same price for both. One is to repair the flashings and any pointing or whatever that may need doing on the chimney and the other is to remove the chimney all together. If you plan on using any of your fireplaces obviously removing it isn't an option.

This cost me around £600 to get done and now im in the lengthy process of waiting for it to dry before I can sort the walls out in my bedroom.

If you are going to use a log burner you don't need a chimney as they will just put a flue through the roof, that may be worth considoring.

Hope this helps!
 
Emjay86 said:
I had this issue just recently on my house, my damp was a lot worse however.

The problem is likely to be the same in that the flashings (lead skirting on chimney) have probably worn on the chimney and as a result water is getting in, albeit a small amount.

There are two ways to fix this and I was quoted the same price for both. One is to repair the flashings and any pointing or whatever that may need doing on the chimney and the other is to remove the chimney all together. If you plan on using any of your fireplaces obviously removing it isn't an option.

This cost me around £600 to get done and now im in the lengthy process of waiting for it to dry before I can sort the walls out in my bedroom.

If you are going to use a log burner you don't need a chimney as they will just put a flue through the roof, that may be worth considoring.

Hope this helps!
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The chap who came said the flashing looked in good condition but it was the flaunching and pointing on the chimney which was in desperate need of renewal and was the likely source of water ingress. Our chimney is a shared (Semi-detached) with next doors so don't think removing it is an option as next door has gas fires still which is why he said he would remove the unused chimney pots and just put vents in and leave me with one for the log burner.

He is doing the same work for the next door as obviously the chimney stack is shared so we're splitting the bill in half which is good. We were quoted £275 for the work which I didn't think was too unreasonable really. Two other roofers were supposed to turn up Fri and Sat but never did so I may just go with the first one as he is a local guy and has already done work for my next door neighbour before and is doing some more for him soon.
 
If you get any lead work done, make sure they don't cowboy it, and do the lead work professionally. Lead work is NOT cheap, and if you get a very cheap price, be suspect.
 
Hmmmmm, had this work done over a week ago now and the damp doesn't appear to be subsiding. If anything the patch has gotten bigger and has spread onto the ceiling a touch too.

The roofer said he was 100% certain it was the failed chimney flaunching that was the cause and he showed me pics where water had been coming inside the chimney stack.

Is it likely that it is just taking a long time to dry fully? I've been running a dehumidifier most days which looks like its drying it out a bit but it comes back if I leave it off.

I informed the roofer and he said he'll have to go into my loft to double check but he said the flashing was fine.
Anyone any other ideas what it may be? I'm going to go up into the loft and get some temp loft boards fitted so there is access to the chimney breast. Atm its just a sea of thick insulation!
 
When we had something similar done, I poked a moisture meter in, in the same spot once a day and saw a 05-1% water content change each day. But the weather was fine.

How are you testing it? By eye?
 
Skiddley said:
When we had something similar done, I poked a moisture meter in, in the same spot once a day and saw a 05-1% water content change each day. But the weather was fine.

How are you testing it? By eye?
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Just testing by eye as you can see the different shades on the wall where it looks (and feels) damp to touch.

Weather has been a bit all over the place really, we've had rain and snow and frost over the past week. Yesterday was the only "fine" day where it was sunny and dry for the most part.
 
the_r_sole said:
if it's a stone wall it can take ages to come out - have you any wet/damp loft insulation out in that area too?
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Its just a normal accrington brick built 1930's semi.

I've not been able to check the loft properly yet unfortunately. Its had the insulation topped up a couple years back so as you would expect I couldn't see any of the joists which put me off going up at first.

I've popped to Wickes today though to get a couple packs of loft boarding and i'm going to pull away the top layer of insulation and try and run a temp walkway to the chimney breast so I can give it a closer look.

It doesn't help that its got a really small loft hatch which makes it a struggle for a chunky fella like me to get up!
 
Just wondering if anyone can help me with this issue still?

Basically I've had the original roofer back two further times to do further work as the leak still wasn't fixed. The first time he came back he said some of the flashing wasn't fixed properly so he has reapplied sealer to it.

The next time I asked him to go into the loft so he can see what the water ingress is like. After seeing inside the loft he said he was going to replace a piece of the flashing at the back of the chimney.

Now it's only been past couple of days where it's been really wet and I'm not convinced the leak has been fixed. When he was up in the attic he started talking about having to take up lots of the slates to do some more work which was going to cost around £300 which I said I wasn't happy with as I'd already laid £275 for something which probably didn't already need doing.

Now wevd had the heating on and dehumidifier on round the clock and it's still drawing water out but the damp patch looks as though it is drying out but when we then the dehumidifier off the patch comes back and looks like it's gotten slightly bigger. Now im going to go in the loft tomorrow to inspect round the area where water was coming in but if it hasn't been fixed do you think I am better off just making a claim on my house insurance? I think my excess is only £150 and it is mostnlikely to be sorted once and for all and I'm getting really narked off that it isn't sorted. Or do you think it's silly to go through insurance for a potential job which is going to cost £300 for the roofer to do. Bear in mind I've no idea if what the roofer has suggested needs doing now actual does need doing or will be the only thing needed doing.

My thinking is the house insurance people will have to fix the issue no matter how big or small and will have to come back out as many times as it needs to be fixed whereas I could end up getting the run around from this roofer if I have him back again.
 
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