Old Paint Pealing Off Plaster Walls

[haxeyb]

Hi

We have recently finished painting our spare room and really stuggled with the existing paint pealing off when we ran the roller over it in places leaving an uneven finish and a mess on the roller

Our next project is the lounge which we are starting shortly and anticipate these walls to be just as bad....

Any suggestions for any processes/treatments that will prevent this from happening.

Thanks hb

 

[JohnD]

how old is the house?



D**T**P*R

 

[haxeyb]

Between 20 and 25 years old.

 

[Richard C]

The paint hasn't bonded; is it coming off right back to the plaster or just down to another paint layer underneath? Are you or the previous owner smokers?

 

[haxeyb]

It is going back to bare plaster.

There haven't been any smokers living in the house for over 4 years but I am unsure if any owners before that were.

 

[JohnD]

that's good. The house is too new to have distemper on the walls.

If it has ever been wallpapered, there might be a residue of paste on the wall. That has to be cleaned off. I find plenty of warm water, just a bit of washing up liquid, and a wide metal scraper. you will find it comes off as sludge on the scraper if present.

Otherwise, there is a possibility some idiot put PVA glue on the wall before painting it, or did not apply a mist coat so it did not sink in properly.

There is a good chance you will have to strip the walls back to a good surface

When painting bare plaster with emulsion, get a clean surface, and apply one or two coats of MATT non-vinyl emulsion thinned with water. You will find it soaks into the surface and does not cover well. This is what you want as it means it is not just lying on the surface but has penetrated well. I usually use matt white for this because it is cheap and hides any patches where you have repaired cracks or holes with filler of a different colour or absorbency. When it has dried out fully you can coat with your favourite coloured paint. silk vivyl or whatever, which need not be thinned. As you have a nice even, sealed surface it will not need many coats.

 

[haxeyb]

Ahhhh...

Well we had been told to try PVA mix over the current paint??

I take it that isn't the best idea?

The walls have never been wallpapered and have probably only ever had 2 coats of paint previously. Are you suggesting that we strip the paint off and take it back to bare plaster?

 

[Richard C]

JohnD has gone where I was heading ; it sounds like whoever did the original decorating didn’t prime the bare plaster (thinned mist coats) before slapping on the finish. If it’s to look any good, I’m afraid your going to have to strip it back but at least it will give you a good base to start from. Whatever you do don’t put PVA on the walls before painting, with people giving advice like that, you don't need enemies Test a little bit of the stripped wall with a couple of 30% thinned coats of white matt emulsion to see how it soaks into the plaster, if it doesn’t there is still a problem; it could be a PVA error that was made 1st time around. If you’re tempted to steam strip, be careful how you use the steamer, if you make the wall too hot locally, the finish plaster will blow off the base.

 

[haxeyb]

Eeeek....

Thats where I thought this conversation was heading... Ok thank you folks. I will now go away and google the quickest way of stripping paint

Thanks for your help