I'm certainly guessing here, but, elastomeric is designed to flex with the movements in the substrate so it has more flexibility than a regular coating of paint. Applying something other than elastomeric on top would be susceptible to all that flex and would likely fail in a short time.

If you are happy with what's on there now, just use the same thing or the Behr product that is compatible with the Behr elastomeric.

 

Yeah, Gymshu is right. Once you have a highly flexible coating like elastomeric on, you wouldn't want to go over it with a less flexible product. The flexing of the base coat can crack less flexible coatings on top of it.

Stick with an elastomeric. Probably best to just use the same product again. The Behr elastomeric stretches up to %600. You need something that can perform similarly.

 

Actually, I think it all depends on why the elastomeric paint was applied in the first place. Elastomeric paints have much greater film thickness than normal exterior latex paints and are often sold as "lifetime paints" so that you'll never have to paint your house again. If that's why you chose to use an elastomeric paint, it's probably not stretching and shrinking at all, and so any exterior latex paint should work well over it.

Let me explain this, and then you can decide if you can paint over it or not...

Also, I just wanted to make the point that elastomeric paint isn't really designed for flexing; it's designed to stretch. It's meant for painting over masonry buildings where active cracks let in rain water or snow melt. The problem is that when that rain water or snow melt gets into the wall and freezes again, it can cause all sorts of freeze thaw damage to the masonry.

Elastomeric paint is very much like that kids toy "Stretch Armstrong" where no matter how much you twist him out of shape, he always reverts back to his original shape. Elastomeric paint is the same in that respect. When it's applied over a crack, then it'll stretch across the crack for as long as the crack stays open. When the crack closes again, the paint pulls back into it's original shape just like the toy Stretch Armstrong.

A normal latex paint simply wouldn't be able to stretch with the elastomeric substrate, and so it'll crack and peel off the elastomeric paint.

Elastomeric paints have considerably greater film thickness than normal exterior latex paints and they are often sold as a "lifetime" paint. Never will you have to paint again kinda thing. If that's the reason you used the elastomeric paint in the first place, then you probably don't have any active cracks, and your elastomeric paint isn't stretching and shrinking like it's designed to do. And, if that's the case, then I don't see any problem with painting over it just as though it was a normal paint.

IF that paint was applied over a masonry wall to keep water out of active cracks, then I would agree with the advice you were given, which is that you can't just paint over it with any exterior latex paint. However, if this elastomeric paint was applied over any kind of siding on a normal house just to get a long lifetime paint, then it's probably not stretching and shrinking anywhere, and I don't see why any ordinary exterior latex paint wouldn't work well over it.

 

Absolutely correct.