How to Waterproof a Birdbath. Protect your birdbath from the elements while you give it a nice glossy shine by waterproofing the fountain with a sealant. No matter the materials used in your birdbath creation, eventually moisture will begin to penetrate the fountain's surface and moisture often leads to damage. A sealant placed over the surface of... Table of contents How to Waterproof a Birdbath Things You'll Need 00:52 Music by HookSounds http://www.hooksounds.com/