Homeowners can remove caulk by applying a caulk-removal product, allowing it to sit from three to 24 hours and then using an inexpensive caulk-removal tool. They should use needle-nose pliers to grasp any remaining caulk and pull it from the crack, then clean the area thoroughly before applying more caulk.
When new layers of caulk have been applied over old layers, the removal job becomes more difficult and extending the time for the removal product to work is especially beneficial. If there is a single layer and it is relatively new, the minimum recommended time is usually enough to soften the sealant for easy removal.
While professionals often use a utility knife to cut through the old caulk for removal, this process takes a steady hand. As of 2015, caulk-removal tools that have safety guards to prevent the user from gouging the wall or the fixture cost less than $5.
Before applying new caulk, the area should be free of any residue or mold. Homeowners can clean the surfaces with rubbing alcohol using a toothbrush, rag and scrubber sponge. If mold is present, people can mix 1/3 cup of bleach with a quart of water and scrub the area with the solution to kill the mold. It's important to rinse and dry the surfaces before applying a bead of new caulk that contains a fungicide to prevent the growth of more mold.