Major re-plastering job or can it be painted over? Piccies

[Lupa Monkey]

I hope someone can advise me. We've had a little damp problem in our living room for a few years now. It started with the paint blistering. I sanded it down, slapped on a bit of damp seal and painted over it. It seemed to do the trick for a while. It is an internal party wall and the patch is about 3.5' above the skirting.

It came back again so I repeated the same thing.

Well it's happened yet again. Only this time round, while sanding back I noticed that the problem was a little more extreme. I ended up pulling off loads of peeling paint to reveal a lovely big bald spot about 2' x 3' with patches of white causing the blistering. Salts I believe?

I brushed on the damp seal as usual but the blistering appeared again within a day and the coat of damp seal didn't bond properly and just peeled off in one big sheet and felt like a deflated baloon

Here is the patch:

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• Lupa Monkey
• 17 Jun 2011
• 1

You can see were I painted on the damp seal (The yellow is the previous wall colour).


And here is a close up of the salts bubbling up to the surface:

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• Lupa Monkey
• 17 Jun 2011
• 1

Is this going to be a major re-plastering job, or is there something I can use to stabilise the salts so we can just sand it and paint it?

Obviously we'd like to sort out the damp properly, but funds are a little scarce at the moment



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[roughcaster]

One of the worst things for pulling salts/efflorescence out of old brickwork/walls is gypsum plaster, which is what i would say is on your wall. Most people on here would advise removing the old plaster back to the brickwork, clean/brush it down to remove dust etc, then scratch coat the wall with a 3 or 4 to 1, sand and cement scratch coat with a waterproofer in the mix. This scratch coat will stop the salts etc from coming through. Let the scratch coat set and cure for a couple of days, then you can either render top coat the wall and then finish it with a finishing plaster,(multi finish), or,,, you can plaster the wall on top of the scratch coat, with bonding coat or hardwall undercoat plaster, and again finish it with multi finish. Another important thing to make sure of, is that any ongoing damp problem is rectified before you re-plaster. You said it was an internal party wall that is the problem,, was there ever an old fireplace located in that position in the past??? Painting on a sealer will not cure the problem at all Amanda,, but see what the other guys on here have to say about it too.

 

[Lupa Monkey]

Most people on here would advise removing the old plaster back to the brickwork, clean/brush it down to remove dust etc, then scratch coat the wall with a 3 or 4 to 1, sand and cement scratch coat with a waterproofer in the mix.

Yup, that's what I was afraid of!

You said it was an internal party wall that is the problem,, was there ever an old fireplace located in that position in the past??? Painting on a sealer will not cure the problem at all Amanda,, but see what the other guys on here have to say about it too.

No, it's quite near the corner of the room so not where a fireplace used to be. Yeah I was aware that I was just trying to cover up the problem and hope it would go away

 

[joe-90]

That's a serious amount of damp and you need to find the source. Leaky pipe under the floor? Guttering overflowing outside? Take a look at it from your neighbours house - do they have a problem too?

 

[NickB_99]

That's a serious amount of damp and you need to find the source. Leaky pipe under the floor? Guttering overflowing outside? Take a look at it from your neighbours house - do they have a problem too?

Agree with Joe & Roughcaster.

I had a damp problem in my porch I sorted a few months ago.
Few salts etc showing above skirting height on each side. I remedied it as Roughcaster described - been fine since.
However, in my case I think was a not very effective DPC (if any) in a non-heated porch. The pics you show look very localised and far more salts than I was seeing.
Talk to the neighbours - it must be fixed before a repair.
How well do you get on with your neighbours?
You never know, if it's a plumbing problem on their side, they may have to get a spread in and for the additional extra, may get your patch sorted too for you. The repair you'd need isn't massive. The section could be cut back and repaired and depending on size of the wall, reskim the wall or blend in.

 

[jrplastering]

do you have a down pipe round that area (outside) it could be leaking and constantly soaking the brickwork which is drawing it in or it could be split under the ground and soaking the ground and again the house is drawing it up.
proberly best to have it off find the source of the damp and waterproof render it and re skim. or you could use thistle lime lite or dricoat.

 

[Lupa Monkey]

This wall is ground floor, internal and nowhere near pipework. Both my room and the neighbours' are back living rooms. So any plumbing/pipework etc is located way away. I don't think that is an issue. The guttering outside appears to be doing its job.

No idea what's going on in the neighbours. For a few years that was an 80 y/o lady who had loads of boxes piled high in that room and we did wonder whether this was creating damp. Sadly she died last year and the house has been bought by a builder who has gutted the place. It might be a good idea to see if he has had a problem on his side. Good idea DIYnewbee99. I'll ask him next time he is there (he doesn't live on site).

Looks like we'll have to bite the bullet and strip back the plaster to the brick. Might have to start a kitty for that. No holiday again next year

 

[Lupa Monkey]

Just a quick update on this problem from a year or so, hope no-one minds me bumping it. We still haven't sorted the problem. Still waiting for our plasterer to come and see it!!!

This is a party wall so no outside guttering to worry about. The builder next door finally finished the refurb and he didn't have any problems on his side.

Is it just a bad mix of plaster that didn't dry out?

Still wondering if we need to hack back the whole wall or just the patch which is effected.

Thanks again for any replies.

 

[HERTS P&D]

Waiting for 2 years!

Get a new plasterer!!!

Andy

 

[roy c]

Have a look at the information that roughcaster gave you and do what he says,,,,

 

[Lupa Monkey]

Waiting for 2 years!

Get a new plasterer!!!

Andy

Not quite Andy, we put the whole thing on hold. We ended up doing a completely different room instead. But we have been waiting over a month for him to come back to quote for this job, so yes an new plasterer is on the cards.