how to treat damp ?

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Braincrank

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Hello all, I was wondering if anyone here has any tips about treating a damp patch on a wall.
We moved into this place about a month ago and there's a damp patch in the kitchen on a pillar between the window and the outside door.
The home owner replastered that bit just before we moved in and on a daily base you could see the paint falling off in a fine powder until it's now flaking off and the plaster is come lose again.
It's a strange place to have damp and I just can't seem to find the cause.
I've got some of this Ronseal damp proof paint but I also saw some paint on the internet that is supposed to be breathable and is used in basements and old buildings but it cost an arm and leg.
I probably have to take some of the plaster off again and redo that patch before I put paint on.
Has anyone got any ideas of what I should do ?

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That look like boxed in pipe work, to conceal water pipes?, , is the wall hollow sounding when you knock on it with your knuckles.

Dec
 
More pictures please, inside & outside.
Inside, step back a bit so we can see the relative positions of the window & door.
Outside, the same, but also close ups of the window & door frames where they abut the wall
 
Sorry to hear this, especially after having moved in recently.

Although you are treating the damp, you should only do this ideally once you have found out what is the cause of the damp. Is there a gutter pipe on the outside wall or as you mentioned if it's old building it may not have a damp proof course in the wall.
 
Very likely to be a leak, you'll have to rip out the boxing-in to see where it's coming from and get it fixed, then you'll redo the boxing-in, dependant on the actual size is use moisture board MDF (got a green filling).
 
Could be rising damp, does it seem wet at the bottom yet dry at the top?

Te plastering suggests a long term problem, paint comes off if applied to wet plaster mind

A local damp specialist should be able to diagnose the problem foc and repair for not a lot of money, a little moisture goes a long way.....
 
I'll do some more pics tomorrow when back from work.
It's a solid looking and not hollow sounding piece of concrete pillar between the kitchen window and the door frame.
There are boxed in pipes running up and into the ceiling therefore I don't think that there are pipes inside the concrete.
It's just strange that its one patch about chest hight (ca. 150cm from the floor) .
More pics tomorrow afternoon.
 
dependant on the actual size is use moisture board MDF (got a green filling).

If it's going to get plasterboarded and skimmed then vapour-shield board (foil backed) is much better than MDF.

If it's brickwork/blockwork and the wall is a cavity construction then the cavity could be blocked allowing damp to travel to inside skin. Lots more pics will help. (Inside & out)

Ant.
 
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I have just purchased a couple of old cottages with various evident damp issues as an investment / rental. I was preparing to install a chemical damp proof course until I saw this site. There is a lot of reading there but it certainly has me reconsidering what I thought I knew about damp issues and the correct remedy.
I am going to carry out a little more digging (literally) before I proceed but correcting any potential sources of water is the correct approach before applying any impermeable surface finishes.
 
On the basis that it's spoiled in that area I'd hack it off to see what it reveals. If you "score" across the plaster where it's good, you'll get a clean edge, and remove the bad.

If he replastered it it was for a reason

- wet brickwork from penetrating damp?

efflorescence? What is Efflorescence | Tips for Treating Salting on Plaster and Preventing Efflorescence from Reoccurring | DIY Doctor

a leak? (though it doesn't look like a typical leak where you'd expect brown water marks).


Tricky these things can be.
 
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Make sure that proper finish plaster has been used...not bonding, which will just soak up moisture in the air.
 
If it's going to get plasterboarded and skimmed then vapour-shield board (foil backed) is much better than MDF.

Think you've misunderstood me, I was suggesting to use MDF to box-in as opposed to plasterboard. Run a bullnose down the leading edge, paint it and job done.

Also easier to get access to pipes behind in future using MDF/wood, really never used to like the idea of boxing in using plasterboard/dry line.
 
The plaster could possibly been hacked off and replaced before the wall has dried out fully. If that's the case once plaster is wet it's knackered, so as somebody suggested i'd remove the plaster and let the wall dry out fully whilst making investigations to the cause.
 
Right, here are some more pics .
If its rising damp then why is the wall bone dry at the bottom and the patch is half way up the wall ?
Wouldn't it be at floor level ?

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At the moment its raining cats n dogs therefore I will do a bit more research and will tackle it once/if we have another dry spell (-:
 
The box on the right hand side is where the pipes go up in but I can't find any obvious leak.
Will have to take it apart and inspect it once I tackle the job .
 
Whole wall looks wet judging by the rusty external angle bead
Have a look where the door frame & window frame meet the external render - do they need sealing around the edges?
Couple of good coats of sandtex externally may solve the problem.
Could also be a condensation issue. Looks like it is possibly a 9" solid wall which will be cold. Check for surface condensation when cooking in the room particularly when weather is cold.
 
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Update : after doing a bit of poking about at the outside wall it turns out that the wall is in a pretty poor state. Seems the moisture has crept behind the pebble-dash and was nicely hidden behind a layer or 5 of thick outside masonary paint.
I can actually press the pebbles in with my thumb and it's only the thick layer of paint(s) that's holding everything together :-0
Looks like a big(ish) job for the summer then ....
 
Strip the dashing off and let the summer sun dry it all out.

Ant.
 

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