How to Caulk a Shower and Where the Bead Should Go

Give the replacement a clean foundation

Peeling caulk, cracks or missing pieces mean it's time to replace the bead. We'd put surface preparation ahead of application technique, because leftover caulk and moisture keep the new sealant from bonding properly.

Your tube's directions control preparation, application and curing, and your shower or surround's installation guide overrides general placement advice if it has specific requirements. Check applicable local requirements before beginning.

Where the bead belongs

Put the replacement bead in the joint where the shower meets the wall, in inside corners where two walls meet, and along seams where the walls meet the shower floor. Follow each of these joints wherever you're replacing old caulk, filling the gap itself with the new bead.

For a tub shower, include the seam between the tub and the wall, including where wall tile meets the tub. That gap gets exposed to water, and sealing it helps keep water from getting behind the tub and damaging the surrounding materials.

Check the gap's dimensions before preparing the bead. Bob Vila limits its general caulking method to joints no wider than 1/4 inch and no deeper than 1/2 inch. Keep this method within those limits.

Choose a sealant made for the job

Look for a waterproof, mold-resistant sealant labeled for kitchen and bath use. GE recommends 100% silicone for showers because it stays flexible, is durable and repels water and moisture.

You have other formula choices, too. DAP's Canadian shower guidance includes the latex product KWIK SEAL ULTRA and accepts silicone or hybrid formulas as alternatives. That latex example is for the Canadian market.

Handling matters when you're choosing between suitable products. Bob Vila describes silicone as forming the stronger seal and latex as easier for beginners to work with, with silicone-and-latex blends such as DAP Kwik Seal Plus offering a compromise.

Take out the old bead

Strip every joint you're replacing completely, including the small remnants left after the main strip comes away. Don't cover the old bead with fresh caulk: the old material interferes with adhesion.

1. Carefully cut down the middle of the old bead with a utility knife. Keep the blade from scratching the shower as you open the caulk line.
2. Pull the loosened strip away with your fingers to expose the joint underneath.
3. Remove the remaining caulk with a joint scraper. Use silicone caulk remover or mineral spirits on stubborn areas to soften the material or remove residue, leaving the joint free of old caulk.

Give caulk remover time to work before scraping the softened material away. Wipe with a rag or paper towel afterward so the exposed area is ready for cleaning.

Clean the joint and inspect underneath

Wash everywhere you plan to seal with warm soapy water to remove grime, soap scum and mildew. Use a scrub brush where needed, because it cleans more effectively than simply wiping the surface.

If there's mold in the grout along the wall-to-tub gap, treat it with a mold-killing product, scrub and rinse with water. Dry the cleaned area with a clean towel, then allow a few hours for air drying.

Wait until the surface is completely dry before applying sealant. Dirt, product buildup and moisture interfere with adhesion. For Canadian KWIK SEAL ULTRA, that means no application to a wet or damp surface.

Set up the edges and nozzle

On the dry surface, place painter's tape on both sides of the joint if you'd like help keeping the edges tidy. This is optional, but especially useful with sticky silicone. Use the widest part of the gap to guide the spacing between the strips.

We'd use GE's 45-degree nozzle cut with an opening slightly smaller than the gap, because you can then control bead thickness with trigger pressure. Cutting off too much of the tip gives you a wide opening and a thicker, messier bead.

DAP's alternative is also a 45-degree cut, but with the opening matching the gap width. After cutting, puncture the cartridge's inner foil, if present, with the attached pin or a long nail, then insert the tube into the caulking gun.

Keep the bead steady and filled

Start in a corner and pull the applicator smoothly away from your starting point, holding it at 45 degrees as in Loctite's method. Keep your trigger pressure and pace steady so the sealant comes out evenly. Fill the joint along its length, avoiding stops where possible.

If pushing feels more natural, Bob Vila accepts either pulling or pushing forward with the gun at 90 degrees. American Home Shield pairs that 90-degree push with a different nozzle setup: a blunt 20-degree cut matched to the gap, with a small bead pushed just ahead of the tip.

Use enough caulk to fill the gap without piling on excess. An overly thick bead looks messy and can take longer to dry. Disposable gloves are optional during application if you'd like to keep sticky caulk off your hands.

Smooth and unmask while it's wet

As soon as you finish a section, smooth the fresh bead with a caulking tool or a gloved finger, removing excess sealant. This helps it adhere and leaves a clean finish. Work promptly, before the surface begins to dry.

For the wet-finger method, wet your finger with water and move gently along the line in one smooth pass to form a rounded bead. Don't use soap for smoothing, because it can affect the sealant's integrity.

Carefully peel away the painter's tape while the caulk is still wet, then move to the next section. Look for a filled, smooth line: unsmoothed caulk can leave gaps or rough edges that trap dirt.

Give the new seal time to cure

Keep the bathroom well ventilated while the bead dries and cures. A surface that feels dry and a sealant that's fully cured are different stages, so use the tube's full-cure time to plan when you'll return the shower to use.

Bob Vila calls for at least 24 hours before regular shower use. American Home Shield describes full curing as taking 24 hours or more, while some GE sealants allow water exposure within a few hours. The exact timing depends on the brand and formula.

For this replacement job, leave the shower unused until the sealant has fully cured, even if the tube lists an earlier water-ready time. Keeping moisture off the new bead during that wait protects the fresh seal.