masonry paint peeling off

[hasbeen]

'Morning All,
About 3 years ago I painted the gable wall of a 15 year-old house.
The customer wants the whole house repainted following some building work, but there's a problem with the gable, which is divided by 2 bell castings: On the middle third, all the paint (not just the top 2 coats I applied) is peeling & blistering.

I prepped the wall thoroughly (Bleach then pressure washer then allowed to dry thoroughly), but I can't recall the condition of the existing paint back then.

I's the wall that gets the prevailing Cornish weather & the customer had had some damp in the bedroom, which she had treated with dampseal internally. I remember advising her to get the chimney flashing & tiles checked for water ingress, as the top & bottom of the wall were unaffected, but......

So, if the previous owner had the same problem they might well have used waterseal or similar on the outside surface?
In which case, what should I use to prime the bare surface? Bearing in mind that it's just the middle third of the wall that's affected?

I could really do without having to return to this job in a couple of years. You know the old adage "Bad News runs 'round the world while Good News is still getting his boots on" - Never truer than down here!

Pete

 

[joe-90]

Damp seal can be over-painted. Could be PVA in the render? Try alkali resisting primer before over-painting.

 

[toneekc]

Sorry I ment

What's under the paint, is it render, render and brick, render and lathe?



T

 

[hasbeen]

Sorry for the delayed reply - Good render under the paint: The place is only 15 years old.

 

[hasbeen]

Thanks Joe, I think the primer's going to be the way to go - At least the customer will know I tried something.