Caulk removing tool or putty knife (to remove old caulk and debris) Household cleaner or rubbing alcohol A stiff wire brush (if repairing masonry or concrete) A clean, dry cloth or (lintless) paper towels Painter’s masking tape A backer rod (if the gap is more than 1/2″ wide or deep) Caulk gun (A caulk gun is not necessary for smaller jobs that can be finished with squeeze tubes.) Mineral spirits or isopropyl alcohol (when using silicone) Gloves