Sealing Concrete Under Cabinets . Use a bubble level to make sure your concrete floor surface is horizontal. Apply a second coat in the other direction, let dry. Removing Countertop Stains & Concrete Countertop Sealer Concrete from www.pinterest.com Allow the sealer to dry for one to three hours between coats. And keep just a hair of cabinet toe kick showing for the top tape line. Concrete sealers are chemical substances that protect the garage floor surface from water damage, stains, oil, moisture, extreme temperatures, and other contaminants.