Mysterious damp problem - need help

[fergju]

Hi

We are currently renovating a property in Sydenham. We a damp patch on an interior wall and the floor board below it. It starts to dry out and then heavy rain comes back. Our builders have checked all the pipes and can find no leaks. It is an interior ground floor wall that is damp but the exterior walls and floor close to them are dry.

Does anyone have any ideas? Our builders have lifted the boards but cannot see anything specific.

Do i need a damp specialist and what are they likely to be able to do.

Thanks

[Mazza6]

Is there an old unused pipe in the wall that hasnt been capped off properly? Good luck.

[fergju]

Sadly not that's all been investigated.

Looking outside under the central drain cover looks like water from upstairs isn't flowing properly into it maybe but I have no idea who owns the drain is it me or the council?

[ladyblue]

Have you had you're drains looked at if not give dave from down the drain a call his number is 0208 314 5244

[AbDabs]

Is it near a chimney, blocked off or used? There may be rain coming down the flue and then it finds its way through any missing mortar between the bricks in the wall.

Or is it possible that it's just that the plaster has become hygroscopic? - When you have heavy rain the atmosphere becomes damp and any hygroscopic plaster will soak it up.

[fergju]

really have never heard of that think I am going to have to call someone in to take a look

[JimiSayo]

Angela Lyon is a Chartered Buildings Surveyor with an intricate knowledge of property and buildings amassed in almost 40 years. I know she has a lot of experience with damp issues, sourcing and dealing with it. Give her a call and she'll come out and have a look.

You can reach her on 0208 679 6363

[ed_pete]

I can recommend David Duggan for damp problems. Several recommendation on the EDF for his services. His number is 07943 804075

[Richy86]

David Duggan did a proper botch job on my place. Don't use him.

[Herne Hill Guest]

I'd advise getting more than one person in to inspect. I had a complete fantasist round to mine. I had a damp patch which I couldn't explain and took my time over as it's rare for water to leak down a chimney and rising damp didn't make sense. Turns out that my first floor next door neighbour, who I am downhill from, had pierced a radiator pipe and the water was slowly seeping through. It would never have been discovered only my neighbour on the ground floor had some plastering done which would not dry. We also have a very high water table as we are at the bottom of a hill so it's often dampish. East Dulwich has lots of compacted clay gardens so it all contributes.

[citylover]

I just put a reommendation up for Keith Gardener on this forum, he's great, he works out the source of damp, he got to the bottom of all the damp parts in my house and told me how best to deal with each one. He's so knowledgeable, he actually made damp interesting!

[HHBilly]

Hi

I am having a similar problem but the cause has been found. My cellar was flooding after heavy raain. Problem was a big leak next door that had been going on for many years and the ground had reached saturation point. I started by getting Thames Water to check supply pipes under front path and they could clearly hear the leak was next door.