1. Choose the Right Caulk
Caulk that keeps air and water out over time is a necessity when sealing around the home. For a long-lasting seal, choose permanently waterproof, flexible, shrink-crack-proof 100 percent silicone. Avoid using acrylic caulk, which can shrink and crack over time. Air and water can seep through gaps left by cracked caulk. Those leaks can lead to water damage, mold growth, and higher energy bills.
2. Clean the Surface
Remove old caulk, dirt, and loose particles with a caulk-removing tool, or a wire brush for concrete and masonry applications, and wipe clean with a cloth. Apply masking tape to either side of the joint to create a straight edge. (Remove immediately after caulk application.)
3. Prepare the Tube and Seal
Cut the nozzle to desired bead size. Pierce the inner seal with a stiff wire or other similar object. Insert cartridge into caulking gun. Seal around unsightly cracks or spaces inside and outside the home. If using a caulk gun, squeeze with even, consistent pressure to control the rate at which the caulk leaves the tube.
4. Smooth the Caulk Seal
Use your finger or a wet caulk-smoothing tool within two to five minutes of application.
5. Store the Tube and Clean
Squeeze the caulk until it’s barely coming out of the tube. Replace the cap, or use a nail in the tube opening. Wipe hands with a dry cloth before washing with soap and water. To clean the area around the caulk, use mineral spirits for silicone caulk, and soap and water for acrylic.