I personally use Redgard in my bathroom. The fiberglass in the product helps protect your shower like sealant used in the bottom of a boat. Nothing will get behind it! It bonds straight onto the surface to create a moisture vapor barrier. Keep in mind, it is fiberglass so it does off-gas for a day or two after applying. You’ll probably want to go away for the weekend after you use it in your bathroom to avoid the fumes.