Painting problem

[expat paul]

Hi,
I have just spent a good day sanding and cleaning the previously painted ceiling (plastered) and walls (plaster bricks) in my bathroom. Late last night I tried to apply an 'sous couche platre' (I live now in France I think its best translated as a primer undercoat for plaster) with a roller but old paint flaked off and either stuck to the roller or the new paint on the wall.
Anybody know why and the best method to cure the problem ??. I tried to scrape off the old paint but not much came away.
Thanks

 

[Nige F]

it`s been done previously with a limewash Le wash de lime........ maybe they have stabilising solutions for masonry paint over there

 

[expat paul]

Would a very dilute solution of the infamous PVA work ???

 

[spice]

Yes the infamous PVA will work in this case.
what you have to do is to sand it all again, and get rid of any flakey bits that left on the ceiling.
try and sand it back so there is no jagged edges of the old paint showing.

After you have sanded it as smooth as you can, then knock up some diluted PVA and whack that on the ceiling.
This will stop any more of the flakyness or peeling of the paint.
When dry, fill and make good where necessary, but after you have rubbed the filler down, whack some more diluted PVA on the filling.

Leave to dry, then emulsion, and it wont flake, but I would suggest that even though its been previously painted, I would still thin down my first coat of emulsion, then carry on as normal.

 

[expat paul]

thanks