HELP! Damp patches downstairs, damp or roof leak or both?

23 Aug 2010
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United Kingdom
Hiya everyone,

Hope someone can help us as we are at a loss. Basically we have 3 damp patches on a couple of walls downstairs (2 around 1 meter high, the 3rd near the bottom of the adjoining wall), either side of our chimney breast and one on the adjoining wall. The damp problem is a lot more evident when it rains but there is no evidence of damp upstairs around the chimney breast. We have had a few quotes from damp proofers, 1 said it is damp, a second one said it's not damp, that it was too wet to be damp and that the problem would be a leak from a roof! So we asked a couple of roofers, 1 said yes it would be the loose chimney flashing causing the damp patches, another said it would not be the chimney as if it was the chimney then upstairs would be damp around the breast too (which it isn't).

Anyone got any ideas?

Thanks for any help

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how do you feel about heights? Best thing you can do is get up on your roof and check over the chimney flashing and haunching.
Don't trust any damp proofing companies. My brother has been working for one recently and even he says they are just out to scam people out of their cash.
Typical job,,, Materials £60- £100. Labour £200. Cost to householder £2000. And the managers of the company are only bothered as long as the cheque clears. They are not bothered if the job is done properly just as long as the customer pays. Over half the jobs he's been on didn't even need doing by his reckoning.
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Hiya everyone,
Thanks for the feedback so far, had another damp guy here this afternoon and he says its definitely damp and mentioned the salts in the wall?

In reply to everyone's posts I'm going to try and have a look at the chimney tomorrow if I can borrow some ladders.

And the house is approx 100 years old and had an injection damp course (I think, I did not live here at the time) but I know the damp course was only done in parts of the house.
There is one more spot of damp, it's floor level, a small line about 10 inches high right next to a radiator.

Thanks for all the replies so far as I'm a complete novice! It's nice to know people will try and help
there's a strange boxy thing on that wall. Is it a sawn-off chimneybreast or flue?

Where is the bathroom and plumbing in relation to those damp patches?
It's boxed in water pipes mate but it doesn't seem like it's them as the damp is on both walls and only appears when it rains.

Bathroom is on the same floor the other side of the house.
'mmmm, wet patch on the boxing in round plumbing? Open up the box and look inside.

Does anyone drape wet washing about the house?
Yeah that's what I originally thought and we had a quick look but it's dry all around the box and we could not understand if it was the cause why it would be on the other wall too?

As for the washing we do but not for months and it's worse than ever at the moment mate.

Cheers for this
wet patch on the boxing in round plumbing?

How can you not open it up and look inside?

there might be more than one cause
Damp patches on walls in wet weather are often caused by condensation when it gets colder and more humid. You can also get condensation on cold water pipes in damp conditions

Not saying it isn't the chinmney as well though.
Thanks again John, I shall check the pipes tomorrow, thanks for the help.

I shall post the result! Ha.
i have the excact same problem as you :( there are no pipes anywhere near my wall though .The damp only starts about a metre high off the floor ,i will upload some pics soon to show it beter :D
the damp is around the fireplace wall at the back of the terraced house ,it has a board over the opening and i recently fitted a vent to the front of it.

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