Hi Helen, well, usually the thing that causes paint to peel is usually damp related, plus a thing known as 'efflourescence' thats salt being released from plaster or masonry, and also if paint has been applied to a completely bare surface without being sealed adequatley beforehand.
Im assuming its the paint, and not the actual cement rendering that is blistering, Helen, therefore, the area affected needs to be thoroughly dry scraped and sanded and dusted down, then a couple of applications of watered down pva solution, then i coat masonry pain thinned down with 30% water, then 2 normal coats of masonry paint. Don't forget, brands like crown and dulux have a telephone number on their tins of paint you can use to get any technical advice, dont know if you have ever noticed it, but why not try, see what they say?
Im assuming its the paint, and not the actual cement rendering that is blistering, Helen, therefore, the area affected needs to be thoroughly dry scraped and sanded and dusted down, then a couple of applications of watered down pva solution, then i coat masonry pain thinned down with 30% water, then 2 normal coats of masonry paint. Don't forget, brands like crown and dulux have a telephone number on their tins of paint you can use to get any technical advice, dont know if you have ever noticed it, but why not try, see what they say?
