Painting Bathroom Ceiling, Newly Plastered.

Completey plastered or just skimmed, how long as it been left to dry.

First coat of matt emulsion should watered down, usually I do 70-80% paint to 20-30% water depending on the brand of paint.

Could be plaster use some pva in is mix, so you have grief.

 

Possibly the plaster finish was chust too polished. A well-polished skim is really hard, and emulsion paint struggles to get hold.

What's the best primer to use now on the bare plaster? Something guaranteed to stick?

 

Could try one of the Zinnsser primers...

 

Could also use EverBuild 406 Stabilising Solution, give the ceiling one or two coats.

 

Tee-hee. I didn't want to suggest this, but I've used it myself for exactly this reason - cracking & lifting paint on bathroom ceiling. I haven't over-coated it with paint yet, so cannot say for certain that it's done the trick, but it seems to have stopped further cracking. But I also used it when fixing a crack in the plaster on a chimney breast - scraped out the crack to remove all loose stuff, soaked it in 406 until it drank no more, allowed to dry and then filled. There had been some light stains coming through before, but no more. And the paint is perfect.

It should work - 406 will soak right in to the plaster layer and is meant to give an ideal surface for paint. Just neat emulsion straight on - after the 406 has fully dried.

 

It's a nightmare situation, Tom - one of the jobs I hate more than any.

So that lightened the mood...

The issue comes down to how loose the rest of the paint is. If you find that there are definite loose and definitely 'fixed' areas, then you're lucky. Chances are you could keep on scraping away forever, with small chips able to be picked away with a bit of work.

But, hopefully you'll find that some paint is loose - remove it completely - and the rest is fine, so leave it.

Use a good quality scraper - it should have a firm blade. Sharpen the end if necessary. Even use a wide chisel is it helps!

Hopefully you'll reach a point where you know the rest of the paint is secure enough and want can stop.

Then apply the 406 (if this is what you decide on) with a brush, making sure you apply it well against the remaining paint edge - it should hopefully help adhere and seal these edges to prevent further flaking.

Then it's a case of fine surface filler - apply with a wide filling knife using the surrounding paint surfaces to control the level. Apply a couple of thin coats if this is easier. Then sand using a flat block - probably 300-ish grit? Work away until you get the level flush with the surrounding paint - it should be easy enough.

Wipe clean and roll on a very slightly watered coat of emulsion - 10% water.

See how it looks. If it looks ok with that one coat, it'll be even better with a neat second.

 

You must have put too many coats in too short space of time...and also you should have considered using soft sheen emulsion as your top coat rather than so called bathroom paint. Now I suppose scrape off what's peeling then prime it with something like Zinsser 123 and then use proper paint this time .

 

rimce44, Why soft sheen in preference to Bathroom Paint, please explain?

 

Bathroom paint as they call it never live up to the expectations. I have painted once where client bought his own paint. Had to repaint it about a week later as it became stained from the water running down the walls. On the other hand soft sheen is not too shiny and give you nice washable finish.

 

I guess it really depends on the quality of the paint. Just a suggestion: the client will always go with the cheapest solution, so tell them that you will not be held responsible if the quality of the paint is of fault.

 

What it depends on is using the correct paint type for the job!

 

Every time I go on a forum and read waterproof or damp proofing or plastic paint , bathroom paint , i read problems. I suspect that if damp is getting into the plaster at the edges its getting into the plaster and then has nowhere to go because it's bathroom paint. The plaster can't breath. over the shower, and at the window where condensation forms. I may be wrong, I'm not an expert but when your foundation are a swimming pool and there's no plaster left on the walls you tend to start researching and noticing these problems and that they have things in common. or it could be that the plaster is locking moisture in because it has pva in.

 

it wasn't dry completely, before you painted over ...
try using stabilizer , and Zinsser perma white on top ...
and theres nothing to do with pva in a plaster.
try it should work

 

Go with the Zinsser.

I wish our host stocked Everbuid 406,as my nearest cheap stockist is now Salisbury, about 40 miles from me.