What's causing these patches and how do we fix them?

[Puzzledconfusedandbewildered]

These patches have spontaneously appeared in the bottom corner of an external wall. Nothing has been spilled on the wall or rubbed up against it. More seem to be appearing too

What's causing it and How do we fix it? Is it going to be expensive?

[mineofuselessinformation]

Do you have lining paper or wallpaper? It looks like damp to me.

[Puzzledconfusedandbewildered]

No. The paint is straight onto the previous paint (had to do a cheap redecorate when we moved in it all needs replastering)

[isthistoonosy]

What does the outside of the wall look like. Is there a corresponding crack running between the brickwork?

[PlymouthMaid1]

If you have only recently moved then I would think it is damp and the previous owners flashed it over. My exterior wall does similar as I think the dpc needs replacing.

[Sprig1]

It's damp. Have a look outside and see if you can see any obvious reasons for water ingress; broken gutters, cracked brickwork etc

[PigletJohn]

Damp. If it's a solid floor, it might be wet from a leak. If the floor is wood, have a look underneath it. What do you find?

Also look outside at the ground level. Has it been raised since the house was built, e.g. with paving? And is there a source of water such as an old drain, a downpipe, or an overflowing gutter above?

[PigletJohn]

too slow!

[Puzzledconfusedandbewildered]

Thanks all. We can't see anything obvious outside to see where it could be coming from, no cracks no changes to the wall etc. Its odd.

How much does it usually cost to fix this kind of thing. I'm thinking thousands am i right?

[PigletJohn]

you have to find where the water is coming from before you know what it will cost to fix.

For example, if your radiator is leaking, it might be quite cheap.

Is it a concrete floor?

[PigletJohn]

btw if you want to spend thousands, I will come along and squirt silicone fluid at your wall. It won't cure the leak, or bridged DPC, or whatever the cause is, but by the time you find out I will be long gone.

[Puzzledconfusedandbewildered]

I just have visions of being scammed that's all!

Erm yes I think it is. It's not floorboards and it's a 1970s semi. The radiator is on that wall but no obvious leaking from it.

[PigletJohn]

concrete floor?

50p says a plumbing leak.

Where, in relation to that wall, is the kitchen?

Pull up the carpet and feel the floor.

Have you got a water meter?

[unlucky83]

1970s semi - so I guess cavity walls, external wall ...hmmm ....do you have cavity wall insulation?
Apparently not all houses are suitable but when it was being done for free for householders some companies were putting it in to walls that were too exposed...subject to driving rain.
Have a read of this ...www.telegraph.co.uk/finance/property/advice/11411880/Could-the-cavity-wall-insulation-scandal-rival-PPI.html and this www.telegraph.co.uk/finance/property/11485758/Cavity-wall-insulation-crisis-may-hit-three-million-homes.html

[PigletJohn]

Jeff Howell is a bit of an eccentric. Entertainingly, in that 2015 article, he complains about accuracy of estimates, then throws in a made-up one of his own.

The water marks look to me like they are a foot or so above the floor, which is much more typical of a wet floor, especially if long-term wet.

[unlucky83]

Sorry lost track of this thread - Jeff Howell is far from the only person concerned about problems caused by cavity wall insulation. Which and the BBC have both done reports on it.
(I have a problem with a damp patch on a wall in my house - it is under a window. I was chatting to an acquaintance who is a structural engineer (? -maybe architectural engineer - something like that anyway ) about it... and it was the first question he asked me. I don't have - it seems like I probably do have some bridging of the cavity - the window is retrofit double glazed and all the windows and door shows evidence of being a real cowboy job, badly fitted - I could believe that they pushed lots of debris into the cavity, maybe some is caught on a wall tie...
It isn't too bad but it is on my long term to do list - maybe when I eventually have the windows replaced I can check inside without removing bricks ( tricky from outside cos it is rendered -would need patching then probably repainting)...

[MrPoppersPenguins]

We had similar problem when we moved into our house (older house though!). We re painted and patches appeared all over walls. We tried everything and nothing helped! Only thing that finally made a difference was eventually we put extremely thick plaster board round the whole room. This probably just covered the issue but at least our room no longer looks awful! Ours was internal and external walls. We spent a lot having external/internal repairs and went back to bare brick before we finally put up the plaster board then skimmed over that. Hope you find a (simple) cause/solution.