
Ironing staining
We’ve been asked by a customer who’d recently painted their external pebble dash. Brown marks had been appearing all over the surface, no matter how many coats of paint they applied the brown were still coming through. Upon inspection we discovered the brown marks to be iron staining, this is due to a high concentration of iron in the stones which until painted would have been unknown.
Solution
The solution- 2 coats to stain blocking primer need to be applied to the surface to seal in the iron and stop it penetrating the top coat. Once applied the surface is then ready for a finishing system, we applied 2 coats of ‘Dulux weathershield smooth masonry paint’.