diy sos

hi there my problem is this.... i had a conservatory built 2 years ago i emulsioned new plaster once it was dry with a matt dulux emulsion but in four particular places in the room the paint blisters then peels off. in the past i've just scrapped off the paint as far as it will go, sanded then re emulsioned but im gettin fed up now my husband and his dad did the wall its brees block which has been rendered on the out side then plastered internally is there a product which i can apply before emulsioning please help diy disaster...diy sos.

How did you emulsion the wall in the first place?

The first coat of paint on a plastered wall should be a mist coat, where the paint is watered down as the plaster will suck moisture out of the paint and this will cause it to crack and fall off.

Hi Marie and welcome!

mOt is correct, but you mentioned flaking in four specific places which suggests it may be more than just a lack of mist-coat.

Where exactly in the room are you having problems?
Do you have a damp course and how are the windows seated on the wall?
Are the flaky bits behind any furniture?
What sort of heating/ventilation do you have in there?
Is there any build up of earth, rockery etc on the external wall?

(You can see where I'm going on this one!)

Get back to us and I'm sure we'll find you a solution.