How to Seal the Flooring Around a Tub

Contrary to what some homeowners believe, to seal the flooring around your tub you must use caulk, not grout.

Use caulk to seal the floor around your bathtub.Use caulk to seal the floor around your bathtub.
Caulk will seal the flooring and will remain a bit flexible, unlike grout which will shrink and crack. For best results, use the highest-quality caulk you can find that is made entirely of silicone. Caulk comes in a variety of colors and is typically easy to install. Taking the time to seal your tub properly will likely prevent issues from occurring down the road.

Remove any existing caulk that is present. Scrape the caulk away with a utility knife or a razor scraper. Take care not to scratch the tub or floor.

Soak a sponge or pad in mineral spirits and use it along the previous caulk line to remove any remaining material. Dry the area completely when done with a paper towel or hair dryer.

Apply painters tape both above and below the intersection of the tub and the floor. Leave a space in between the tape that is about 3/8 of an inch wide. This gap is where you will apply the caulk. The application of the tape will help you to keep your caulk line straight and in its intended area.

Insert the caulk tube into the caulk gun. Open the caulk tube by cutting off the tip of the nozzle, at a 45-degree angle, with scissors. The hole should just be big enough to fill the joint, which is about 3/16-inch thick.

Place the nozzle in the joint at a 45-degree angle and apply pressure to the gun trigger. Begin to move the gun smoothly and slowly back, applying even pressure to the trigger at all times. Your goal is to keep the gun moving at a steady speed to leave an even line of caulk.

Dampen a paper towel or lint-free rag with water once you have sealed the joint with the caulk. Press your finger inside the towel and apply it to the caulk. Pull your finger along the caulk line in one continuous motion to help the caulk become situated in the joint and to remove the excess. Carefully remove the painter's tape and smooth out any ridges on the caulk that were created by the tape. Allow the caulk to dry for 24 hours before using the tub.

Things You Will Need

  • Utility knife
  • Razor scraper
  • Sponge or pad
  • Mineral spirits
  • Painter's tape
  • Caulk tube
  • Caulk gun
  • Scissors
  • Paper towel or lint-free cloth

Tip

  • Mineral spirits are available at many hardware and home improvement stores.