Only water-based acrylic or latex paint should be used on foam insulation, whether you are using the material for crafts or are painting unfinished walls. Though foam-insulated walls do not require sanding, they can be sanded, as long as the foam has dried completely first.Click to see full answer. Keeping this in view, what kind of paint do you use on foam board? Acrylic paint Subsequently, question is, how do you paint polystyrene foam board? The best paint to use on styrofoam is acrylic paint as it adheres to the styrofoam well. Since styrofoam is so porous, you’ll likely need to use several coats of paint to cover it. Use a foam brush to apply the paint and wait for the coat to dry before adding additional ones. Keeping this in view, can XPS foam board be painted? You can definitely apply Paint on XPS Boards,they will not crack. They have a life span of 50-60 years. And it helps to decrease the temperature by 4-5 degrees, even more. Yes of course XPS board can be used under a deck for insulating the room.Does spray paint melt foam board? Painting foam board However, if you’re painting directly on foam board, too much paint can saturate the outer layer of paper and cause the edges to curl up and detach from the foam interior as it dries, so watch out for that. Spray paint will eat right through some types of foam and basically melt or dissolve it.