Peeling paint

[Emsypops]

What would cause old paint to peel off in sheets?! I'm trying to prepare my kitchen walls to repaint them. Some of the paint is a bit cracked and when I've put a scraper to it it's coming off in sheets like how you would expect wallpaper to come off. It's just bare plaster underneath. Doesn't seem damp or anything. Is this normal or has the old paint been applied badly or something? Also, should I mist coat in now that it's down to bare plaster?

Hmmm that sounds like the previous decorator could have primed the walls with PVA (a big no no I've found after hours trawling decorator's forums!). I would clean the wall with sugar soap and then mist coat it, it may then show up some of the damage if PVA was indeed used!

Technically you shouldn't need to mist coat it as it should have been done when it was at bare plaster stage, and it may even be past that point now. If the wall is not looking great after a mist, you could try a primer like Zinsser Gardz.

There are also other zinsser products that are used to stop moisture coming through if there is any indication that damp may be causing the peeling.

I suspect wrong paint used for mist coat, or no mist coat. I used vinyl emulsion for a mist coat and this is the problem I have. I'll need to take the whole room back to plaster, sand the surface to key it in, then start from scratch with a mist coat using matt emulsion.

At least your paint is coming off easily!

The wall is amazingly smooth and the plaster I've uncovered is like it's never been painted. Not sure whether I should try a mist coat or a primer? Maybe both! I still need to remove more of the paint. Most of it has come off easily but there a patches that are stuck on a bit firmer. Not sure how I'll get them off, steam maybe?

If the plasterer polished the plaster so it was super smooth then a sand would be useful to get a key. Sanding off the remaining bits might be messy but better long term. Then mist coat. I'm not a fan of primers.

They probably pva'd the wall first which is actually the wrong thing to do or the mist coat was just a normal layer of paint so it's not soaked into the plaster properly. Just scrape as much as you can off op then you might want to do a thin coat of cheap emulsion, you could water it down a tad like a mist coat but do a base coat before you then put your actual paint on top x

Agree with the above posters- it sounds like someone used a PVA or other sealant. GEt any loose paint off, and sand the lot back to get all the paint off, and when you get to the plaster, sand it lightly but all over, to give a key into the plaster- it should change colour a bit and look lighter, and feel less slippery. (wear a mask and put dust covers on everything, it gets everywhere).
Test an area with something designed for new plaster, like Armstead Contract Matt, diluted as it says on the pot for the first 'mist' coat (1 part water to 5 paint if memory serves). Test an area by painting/rollering it, letting it dry, then see how sound it is by trying to rub/scratch it off. If it doesn't flake or crack, try a coat of whatever paint you plan to use on top, then see if that dries soundly. If so, you're good to go. If not sand it all back a bit more and test again.