Battle with flakey wall paint

[DIYgirl169]

Hello, I'm a novice looking for advice. We moved into an old cottage and soon after noticed some of the internal walls were flaking away in places, with the paint turning into very fine dust and stripping right back to the plaster. I've had a decorator round to fix it, he tried to by doing coats of stabiliser and then re painting - 1 month on and it's flaking right bck to the plaster again! I would appreciate any advice as I have no idea how to stop this problem! Thanks

 

[JohnD]

It might be distemper. Scrape some flakes off. Put some in warm water, and some in boiling water. Do they dissolve and smell unpleasant?

 

[DIYgirl169]

Just done that, no dissolving from either cup. The warm cup smelt a bit funnier but I wouldn't say unpleasant. The problem appears to be with the wall behind as the paint was fresh on...very confusing!

 

[JohnD]

'mmmm

Is the plaster old and white, or modern and pink? Does it have a glass-like smoothness? If you rub it, does plaster dust come off on your hand?

Is there a possibility it has wallpaper paste residue, or PVA glue, which is very bad?

If an old cottage, it might be damp related. Tape a piece of clear plastic tightly to the wall, see if beads of water or mist appear on either side of it.

If the decorator is an experienced local person, I expect he would be familiar with old cottages like yours, and the materials and techniques, so better able to diagnose. When do you think this flaky paint was applied?

 

[DIYgirl169]

The plaster is pink & smooth, I'm going to try the plastic tip although when we moved in (August 2015) we had a damp company inspect the cottage & they said it was fine. Do I tape the Plastic to the bit of the wall where the paint is rubbing off or anywhere on that wall? I ask as the tape may not stick to the bit where the paint is already crumbling! The paint tends to come off at the bottom by the skirting board. I think I may need a second decorator to come round & diagnose the problem as my first hadn't dealt with this before but consulted a friend who had. Thank you for your help

 

[misterhelpful]

Does it look like any of these Google images? If not, could you post a pic or two?

https://www.google.com/search?q=eff...-APwQ_AUIBygC#tbm=isch&q=internal+rising+damp

 

[DIYgirl169]

Ah, it does look a bit like that. Which surprises me as as I said, Dampco came out and said the house was fine. Here's a pic on the beginning of the crumbling, eventually the paint from the whole bottom corner of the room crumbles away

 

[misterhelpful]

It's efflorescence caused by some form of moisture issue, whether it be damp, condensation or a leak. Moisture within a substrate causes salts to push to the surface of the wall, and then crystallize, as it tries to escape, giving you that powdery crumbly surface. The only way to solve it completely is to address the root cause, and ensure the area is totally dry and repaired, before repainting. You can use anti damp products as a temporary measure, but they won't hold up for long if the moisture problem is still active.

The darker patches suggest the problem is still somewhat active. If it has been solved/treated in the past, painting too soon afterwards could have caused any remaining moisture to be trapped, which would again result in the problem you have. If this is the case, you need to let the patches dry out before painting; applying an alkali resistant primer before repairing and repainting often helps prevent any recurrence, in this instance.