Peeling paint on plaster

[wilroda]

Hi

When we moved into our house the previous owners had replastered the hall walls and there was a new coat of emulsion on. We emulsioned over this with our colour of choice.

About 6 months later we noticed cracking and peeling of the paint. Having made enquiries we decided that the plaster had not been " primed" and we removed the paint very easily - it had not stuck and we were literally able to pick it all off!

We PVA'd the walls and started again with a dilute emulsion followed by normal strength paint.

This was three years ago and initially all seemed fine but slowly the paint is peeling away again and " cracking" in certain areas. Other areas are ok.

When you look at the plaster layer beneath the flaking paint there is a layer of chalky substance on the surface.

What can i do about this? I was thinking of putting lining paper up but someone mentioned to me that oil based primer would do the trick.

Any advice would be much appreciated.
Thanks

 

[Alastairreid]

You should not have used pva on the walls prior to painting with your mist coat.
And the mist coat should be matt emulsion, my usual method on top of new plaster is a couple of mist coats diluted approx 50/50 then top coat next day.

The pva forms a skin on the plaster and the paint is unable to take. this will ultimately cause the paint to craze and peel.

 

[wilroda]

Thanks.

We put the PVA on when it peeled/crazed for the second time, thinking that it would cure the problem.

What do you suggest as a resolve for this?

 

[Richard C]

initially all seemed fine but slowly the paint is peeling away again and " cracking" in certain areas.

That’s PVA for ya; never let it anywhere near a surface your going to paint or tile onto. As to why the original paint failed, could be the previous owners misguidedly used PVA to prime as well, the plaster was incorrectly primed or was over polished by the plasterer.

What can i do about this? I was thinking of putting lining paper up but someone mentioned to me that oil based primer would do the trick.

Lining paper is god awful stuff; it will only be stuck to the paint if the paint is falling off, so will the lining paper eventually! A complete strip of all the paint & PVA (which can be difficult to remove) is the best solution and then prime it properly before painting. Some swear by Zinser primer where PVA has been used but I’ve never used it but, again, you will still have to remove all the paint or that won’t stick either.

 

[roughcaster]

Oil based undercoat as a sealer is always my choice when it comes to stabilising an old plastered surface. You can then decide what you want to do with it after that.

 

[keyplayer]

Some swear by Zinser primer where PVA has been used but I’ve never used it but, again, you will still have to remove all the paint or that won’t stick either.

Zinsser B-I-N for the win, pricey stuff though, and open a window when applying or you'll be zonked.