Ask the Expert Question-and-Answer Archive

by Ron Joseph

February, 2006

Painting Over White-wash

Q. I am using Crown Duracoat on white-washed plastered walls, can you tell me why it keeps blistering and cracking?

A. Without knowing more about your situation I would guess that because white-wash is extremely alkaline in all likelihood the Crown Duracoat was not intended to be applied over such a strongly alkaline (high pH) surface.

If I am correct, you should have first applied a sealer that is resistant to alkalinity, and then applied the Duracoat.

Best wishes,

Ron Joseph