How to Recaulk a Bathtub or Shower

When to Recaulk

Caulk around bathtubs and showers should be replaced when it shows signs of cracking, peeling, pulling away from surfaces, discoloration from mold, or visible gaps. Deteriorated caulk allows water to seep behind the tub surround or shower walls, causing hidden moisture damage, mold growth, and potentially structural rot in the wall framing. Most bathroom caulk should be inspected annually and replaced every 3 to 5 years, though high-use showers may need attention sooner.

Removing Old Caulk

Complete removal of old caulk is essential for the new caulk to adhere properly. Use a caulk removal tool (a specialized hooked blade) or a utility knife to cut along both edges of the old caulk bead. Pull out as much caulk as possible with pliers or by hand. Apply a caulk softener/remover product to stubborn residue, let it work for the recommended time, then scrape clean. Finish by cleaning the joint with rubbing alcohol to remove any remaining residue and ensure a clean, dry bonding surface.

Choosing the Right Caulk

Use 100% silicone caulk for bathtub and shower applications — it remains flexible, resists mold, and maintains a watertight seal better than latex or acrylic caulks. Choose a caulk labeled for kitchen and bath use with built-in mold and mildew resistance. Select a color that matches your fixtures (white, almond, and clear are most common). Avoid using grout in the joint between the tub/shower pan and the wall tiles — this joint flexes with use and temperature changes, and rigid grout will crack. Only caulk belongs in this joint.

Application Technique

Fill the bathtub with water before caulking — the weight of the water pulls the tub down to its lowest position, ensuring the caulk is not stretched when the tub is subsequently used. Cut the caulk tube tip at a 45-degree angle, creating an opening slightly smaller than the joint width. Apply the caulk in a steady, continuous bead along the entire joint. Smooth the bead immediately using a wet finger or a caulk finishing tool, maintaining consistent pressure for an even appearance. Remove any masking tape while the caulk is still wet. Let the caulk cure for 24 hours before using the tub or shower, and drain the tub only after the caulk has fully cured.