Ceiling paint keeps flaking / crumbling

[ahlondon]

There was a leak previously but it's now dry. I scraped away old paint but it kept flaking and crumbling to dust. I then coated it with gloss paint to try to seal it. It lasted a bit longer but it's still coming down. Would damp seal paint work better? I know for wall plaster affected by rising damp you'd need to remove the plaster due to salt but a bathroom leak that has dried should not continue to make the paint react? Ceiling is in hallway above flat entrance door so it's not a humidity issue.

 

[opps]

Are you sure that the leak has been fixed? You could tape some cling film to the ceiling, leave it for a few days and check to see if both sides are dry.

How old is the property?

 

[ahlondon]

Are you sure that the leak has been fixed? You could tape some cling film to the ceiling, leave it for a few days and check to see if both sides are dry.

How old is the property?

I'll try your cling film idea as your reply suggests the explanation would be continued damp. It's ~130 years old.

 

[opps]

I'll try your cling film idea as your reply suggests the explanation would be continued damp. It's ~130 years old.

I asked about the age because the original paint might be distemper. That alone can cause problems if you paint over it with regular emulsion.