I am looking at painting a 1925 house with many layers of cracking paint.I have used a wirebrush on a small area and it comes off in some areas, but not in others. I am also looking to use a pressure washer to take off more. My real question is can elastomeric paint be painted over old paint? Do I have to prime? Can it be used on wood? Hope someone has some ideas and other helpful hits about painting this house. The house is Stucco.
Re: elastomeric paint
I always defer to the paint manufacturers instruction, but generally, you can paint over sound old paint. It sounds like you are getting down to such a surface.
Elastomeric paints are extremely elastic, up to 5 or 6 hundred percent elasticity. They are applied in a very heavy coat, having a spread rate of about 75 to 125 feet per gallon - about a 4th or 5th of normal paints. Two coats are genrally required. A separate primer is not neccessary. Small cracks need to be filled with elastomeric patching compound. Larger cracks in stucco should be chseled out and repaired with stucco patching materials.
The elastomeric paints, with which I am familiar, are 100% acrylic based. Acrylics allow for the shedding of rain water, yet allow the moisture generated within the house to migrate to the exterior, a desirable quality both in wood and stucco sided homes.
Elastomerics are sometimes used on T-111 type siding. T-111 is basically textured plywood and does not hold up well over the long run, as the woodgrain tends to split open. The heavy elastomeric paint can bridge the gaps in the grain. Personally, I would sooner replace the T-111 with a more premium type of siding.