Peeling paint??

[bucksp]

DH and I are redecorating our spare room. We went to sugar soap the walls and found that the previous paint (and the one before that) is just peeling off. It's the most satisfying thing ever but I'm a bit worried about what's going on here. The paint is coming off like peel-off nail varnish and is a balloon like texture. Underneath appears to be plaster with white paint.

Anyone had experience of this and how can we stop the same thing happening to our new paint?

I've never seen anything like that - hopefully someone has and can explain what it is/why it is happening.

Is it Matt paint painted over silk or gloss maybe? Or maybe the walls were PVA'd before painting at one time so it hasn't bonded to the plaster? Or no mist coat when plaster was new/too many thick coats of paint?

Disclaimer: I am not a decorator and am just pulling random bits of info from DIY facebook groups and the internet in general 😁

it seems to be coming off various old paint. I wonder if a paint had been used that does not withstand steamy bathrooms; or if they painted over old wallpaper paste.

there are not many people left who put PVA on walls they hope to paint. Most of them have been killed by angry decorators.

When you've got the old paint off, spray it with warm water and a drop of WUL, scrape it, see if slime comes off on your scraper. Wallpaper paste and PVA do that, as they are not waterproof. If so, wet and scrape all the slime off, rub off any remaining traces with an old towel. Prime the surface with matt white emulsion with 25% water mixed in, see if it grips well, then an unthinned coat of white matt. It's cheaper than your final colour, and will highlight to your eye any remaining defects that need to be fixed (and re-primed) before your finish paint.

If you have a real problem surface, there are special primers you can use, like Zinsser, but they are much more expensive and have volatile fumes.

p.s.

it could even be dirt....

pps

if the base paint is 60 years old or more, it could be distemper. It is somewhat matt, has an unpleasant smell when wet, and dissolves in boiling, but not cold, water.

It is a problem surface.

That looks amazingly satisfying to peel off... if you need any help just call :-P

It's amazing, never seen anything like it.

Thanks pigletjohn, your advice is so helpful. it was getting tough to peel off as it dried out, more flaky. It melts with a heat gun. Tried the washing up liquid and it's suddenly coming off in chunks again.

We think the previous people stripped back the old wallpaper then painted straight over with a vinyl based paint (the dark blue). The light blue paint is definitely kitchen paint as it's everywhere in the house.

Why did you sugar soap the walls? Sugar soap is for prepping painted woodwork. We found latex type paint on our walls under old wallpaper and paint. I think it was used as a damp barrier or insulation back in the day.

Is it because it's bathroom paint? It is anti mould hence the rubbery texture

When they put the house up for sale, the previous owners painted all the rooms with one colour paint- we think it was kitchen paint. It's that what seems to be peeling off now. We think it's because there's some residual wallpaper paste underneath all the layers which has loosened when we've washed the walls down.

We always sugarsoaped and rinsed walls before repainting - didn't realise it was just for wood?

OP I stand corrected. I've just watched the DIY doctor on YouTube using sugar soap on walls!!! I walkways thought it was just for woodwork, sorry! He did say it should be rinsed with clean water or it could react with the paint.

kitchen walls are particularly dirty and greasy, but I have known walls with a dust deposit in the top metre or so that were so dirty paint pulled off on the roller because it didn't stick. Dirt sticks more to cold walls, e.g. in an older house with solid brickwork, but also in bathrooms where it clings to any hint of condensation.