Can Waterproof Sealant be applied to Styrofoam? Yes, all the products are water based containing no solvents or VOC's. It can be applied to Styrofoam. Related articles Use in Concrete Cistern for Bathing? Is this product good for adhering to wood. I'm looking to waterproof a 1/2 whiskey barrel for ponding ? Can the Earlex Sprayer spray the Original Black Waterproof Sealant? How come it feels tacky? Is it cured? Comments 0 comments Please sign in to leave a comment.