Why is the paint peeling?
- Thread starter camerart
- Start date
Sponsored Links
Firstly, was the first coat of emulsion thinned down with water?
Secondly, has any PVA been used?
Secondly, has any PVA been used?
1/Yes
2/Yes, I think so.
Both the man who did the bathroom and the plasterer used some sort of PVA I think. I'm pretty sure it isn't water proof, but don't tell a workman his job (Mistake)
So, I'm guessing that you suspect the PVA is getting damp when the watered down paint is being applied?
I have silicon wall sealer, if any good.
Am I correct that I can still get none water based paints? If so would an undercoat of this seal it?
C.
Sponsored Links
Hi M,
There are lots of differing answers in that thread, but thanks.
It seems then that it's the PVA that's making the paint peel. So how do I treat those patches, please?
C.
Having had another look at your image, I'm not entirely convinced that PVA is the cause of your problem.
Plasterers use PVA to help the skim coat adhere, so that would be underneath the plaster and wouldn't cause this issue. The cause of the problem would be if the PVA was applied to the surface of the new plaster, before painting.
Presumably the initial mist coat was watered down sufficently, but that can't be controlled now.
I can see what appears to be plaster dust stuck to the back of the flaking paint. Is that the case?
If so, it shouldn't be doing that if PVA was the cause, as the PVA would have entirely sealed the plaster, which is what stops it absorbing your mist coats of paint.
It could be that there was just plaster dust on the surface, which has stopped the paint adhering properly, or even that there was moisture still in the plaster which has caused the flaking, as it dried out. If this is the case, scraping off and wiping away all dust with a damp cloth should be all that is necessary to overcome the problem, before applying a new mist coat.
You will probably need to level out the area with some fine surface filling, after the mist coat, then re-mist that filler and paint as normal. Hopefully, this is all you will need to do!
If PVA is the cause, no universal solution is really out there.
You can try scraping away all of the loose paint and sanding the surface, in an attempt to remove any PVA film, then mist coat the bare plaster and continue, as above. Sometimes it works, sometimes it doesn't.
Another option is to use a high grip primer to see if that adheres to the PVA. There is no guarantee that even this will work, and most manufacturers won't recommend these primers for such an issue, even though some may actually work.
Oil based undercoat can sometimes work wonders in all sorts of situations, so if that's what you meant when you asked about 'none water based paints', then it could also be worth a try.
Plasterers use PVA to help the skim coat adhere, so that would be underneath the plaster and wouldn't cause this issue. The cause of the problem would be if the PVA was applied to the surface of the new plaster, before painting.
Presumably the initial mist coat was watered down sufficently, but that can't be controlled now.
I can see what appears to be plaster dust stuck to the back of the flaking paint. Is that the case?
If so, it shouldn't be doing that if PVA was the cause, as the PVA would have entirely sealed the plaster, which is what stops it absorbing your mist coats of paint.
It could be that there was just plaster dust on the surface, which has stopped the paint adhering properly, or even that there was moisture still in the plaster which has caused the flaking, as it dried out. If this is the case, scraping off and wiping away all dust with a damp cloth should be all that is necessary to overcome the problem, before applying a new mist coat.
You will probably need to level out the area with some fine surface filling, after the mist coat, then re-mist that filler and paint as normal. Hopefully, this is all you will need to do!
If PVA is the cause, no universal solution is really out there.
You can try scraping away all of the loose paint and sanding the surface, in an attempt to remove any PVA film, then mist coat the bare plaster and continue, as above. Sometimes it works, sometimes it doesn't.
Another option is to use a high grip primer to see if that adheres to the PVA. There is no guarantee that even this will work, and most manufacturers won't recommend these primers for such an issue, even though some may actually work.
Oil based undercoat can sometimes work wonders in all sorts of situations, so if that's what you meant when you asked about 'none water based paints', then it could also be worth a try.
That makes sense. Plasterers can't always get a perfect finish in corners so it can be quite rough. This means it is often sanded, and if that dust isn't cleaned off entirely before painting, it can result in the problem you have.
I'll keep my fingers crossed that it works out well for you.
DIYnot Local
Staff member
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local
Sponsored Links
