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 What is Liquid Rubber MetalSafe Sealant used for? Can Waterproof Sealant be put on tarred surfaces? How do I cover gaps and cracks? Does the product have a detrimental impact to fish or aquatic plants? How come it feels tacky? Is it cured? Comments 0 comments Please sign in to leave a comment.