Is Liquid Rubber Foundation Sealant safe for drinking water? Currently we do not have a certification allowing this use. Related articles What if I don't want black as my final color? How do I cover gaps and cracks? Can this product be used to waterproof shower walls and base? Can it be tiled over? Can Liquid Rubber Products be used in Drinking or Potable Water situations? Can I build my final membrane all at once? Comments 0 comments Please sign in to leave a comment.