Hi guys,

Had a crack in my living room wall caused by a loose plasterboard and some of the top coat was coming away.

I stripped back the loose stuff, PVA'd as normal and started to skim with Multi-Finish.

All seemed fine, until I dampened down to polish, when the paint started to soften and peel off next to the wet plaster, leaving bare plaster behind it.

I'm a bit stuck as to what to do now. Any got any ideas for me?

Anyone?!

Don't let me down UHM! I've relied on this forum so much in recent years I'm not sure I could cope!

Anyway...

I decided to get some spray on sealer and have used that over the edges of the paint and the nearby bare plaster. Thought if I could stop the water getting in behind, it would solve the problem.

I've then tried to fill with a fairly thick mix of Easi-Fill. It's gone on ok and not soaked the paint, but it's been very hard to get a smooth finish, so I'm looking at a LOT of sanding now.

What does everyone think?

whats the difference between 'suction control' and 'what is suction'?

i trying to be clever...

what i mean is... if there no 'suction' then you need a 'bonding agent'...

if there plenty of suction, you need to 'control' it...

suction is a key.... if you have no suction, you have no key, so you need to create one... known as a 'mechanical' key... next question....

_________________
http://www.peterborough-plasterer.co.uk/

Not sure I understand 100% what you're getting at, but thanks for the reply anyway!

As i understand it, bare plaster has very high suction, so i was using watered down PVA to control it as I have many times before (although usually when I've been doing a full wall skim, not a patch up job). I put my first PVA coat on and let it dry overnight, then did a 2nd coat and left it to go tacky before going at it with the plaster.

As I understood, all would be fine and simple enough to do, as both the bare plaster and matt painted surface had the same level of suction thanks to the PVA layer.

Don't really understand why damping the old plaster caused it's paint to peel in this case. I've patched up a few walls before using this method and it's not been a problem.

dont even remember makin that post the other night..
looking at it, just seems the old paint wasnt keyed well enough to the plaster... prolly never got a mist coat and just wallop, neat out the tub rollered on...
you get the same thing with distemper too.... great well entire ceiling waits till your almost at final trowel then starts to debond... next thing you know its changed its name to 'carpet'...

good cure for distemper is bonding agent, sort of binds it together and sticks it to the wall as well as gives you some sand back as a key..

skimming over paint always carried an element of doubt with it... It happens to us all on occasion and to be honest, all i normally do is cut out the blister, quick lick some pva on it and fill it back in either with a bit of fresh mix or the same mix if theres enough left.... preferably not to 'fatty' so it wont shrink..

i had 3 full walls do that to me over christmas... pva'd, skimmed and troweled up... day later they hanging by the corners, you could poke your finger through the middle, like an easter egg... or just wobble the entire wall... 1 big sheet, give it a tug and its on the floor...
next day the other walls are off too... 1 board wall saved me the whole room
rollered em with bonding agent and skimmed next day, problem solved...

_________________
http://www.peterborough-plasterer.co.uk/

Glad it's not just me!

Think some of the paint in this place might be a bit dodgy. Just started rolling my new Dulux "Blue Perfection" on another wall, and a huge blister appeared in middle of it which I peeled off to find it had taken the previous coat with it.

I think I've solved my original "problem" wall. I got fed up with sanding, realised it was never going to be a good finish, so just PVA'd the lot and did a reskim far beyond the original area I was patching. It's still drying, but I'm confident it will look ok when I've mis-coated tomorrow.

Cheers for the help!