paint bubbling off wall

[mordzy]

Hello, Im not sure if this is the right forum but ive had and issue for years at the bottom of my steps where the paint 'bubbles' (not sure if thats the right term) off the wall. This happens either side of the first two steps neither walls are external. Though the right side is a party wall with the neighbour.

Over the time the paint (matt emulsion) forms small bubbles underneath and just comes off the plaster. its more like the paint is turning into a powder and you can wipe/dust it off with your hand. Its not wet. Ive tried a base coat on the plaster for troublesome walls and then painted over but the same happens. Each year I have to sand it back and repaint.

Below the stars is another set of stairs that goes into the cellar/coal chute area which unused but well ventilated.

Approximately 1m from the last step is the external door. There are no issues with the paint around the door or beyond the steps to indicate its an ingress or damp type of issue.

Any ideas or suggestions would be great.

The house is old. stone construction and built around 1820

The picture is from last year. Ill take some more when I get home

 

[Sunshine32]

That is definitely damp causing the paint to bubble like that. I’ve got the same on the walls of my brick shed (former outside toilet) which is a single skin wall construction and 91 years old. On the wall in my brick shed the damp is rising from the ground as when they built these buildings they didn’t put a damp proofing membrane in. The walls have been rendered and painted but the render and paint just soak up the moisture as it has nowhere else to go. This results in the bubbling of paint and when touched it feels and looks powdery. Fungus then grows on the damp parts and in my case the wall is going green.

 

[mordzy]

Interesting. So the damp is probably rising up through the cellar walls? The wall feels colder to the touch where it peels to where it doesn't. Nothing ever grows on the wall and I dont get any telltale mould you'd expect from damp.

I can stand under that step and look up. The stone is very dusty, crumbley but I dont think its wet. How could I stop this?

Ill take some pictures above and below tonight.

 

[Sunshine32]

Well you have to find the source of the water ingress first and fix that. Then replace any materials which have rotted or are damp. Once the plaster has dried out completely, it will probably blow or have blown already.

If the damp is rising up the walls from the ground it may be worth putting in a damp proofing membrane in-between the brickwork, but I’m not a builder so I would head over to the Screwfix Community Forum and ask there. They are pros!

 

[Sunshine32]

https://www.homebuilding.co.uk/advice/tanking-and-making-a-cellar-dry

 

[mordzy]

I’ve taken a couple more pics. Can’t see any ingress. The wall that flakes is the party wall, not external.

 

[Sunshine32]

Then perhaps the water is coming from your neighbours side of the party wall? Or your cellar needs waterproofing? Sent a link about this. I’m no expert, I’d ask the experts over on the Screwfix forum as suggested. Put all the pics in your post. The more pics, the more they can help.