How to Caulk Bathtubs

Keeping bathtub caulk up to date can save plumbing bills. How? The less water behind your tub and its surround, or under your bathroom floor, the longer everything lasts. Add to that a bathroom that smells good with no mold or mildew problem, and it's well worth your effort to keep bathtub caulking pristine.

Things You'll Need

• Utility knife, caulk remover knife or old flathead screwdriver
• Caulk smoother or popsicle stick
• Appropriate caulk for your surfaces
• Caulk gun (unless you're using self-applying tubes of caulk)
• Gloves
• Sponge
• Rubbing alcohol or caulk remover
• Paper towels
• Mildew and mold eradicator (optional)

Instructions

1. 

   Remove old caulk. If you use the utility knife, do not scratch tub or tub surround surfaces. A flathead screwdriver works, too, but may be ruined in the process, especially if the tub surround is grouted tile.

2. Examine for signs of mold or mildew, which appear as discolorations to the old caulk, tile grout or tub surround. Properly apply mildew and mold eradicator and wait the prescribed time. Thoroughly scrub and rinse the areas, then let dry entirely.

3. Fill the tub with water, so it sinks to its in-use level. You wouldn't want the new caulk to separate when the tub is used. Double-check that the surfaces to be caulked are dry, wiping away any splashes.

4. 

   Load a tube of caulk into a caulking gun or get out the self-applying tube of caulk. Look at the seam to be caulked and estimate how wide a bead you will need. Cut the caulk tube at an angle to the right width for your job.

5. Holding the applicator at a 45 degree angle, squeeze out caulk under steady pressure while moving along the seam. Fill the entire exposed seam. As necessary, wipe excess caulk from the tip onto paper towels.

6. Smooth the seam, hiding any imperfections, with a caulk smoother or wet popsicle stick, or dampen your finger with liquid dishwashing soap and complete the bead. Thin gloves are nice to keep sticky caulk off your hands.

7. Let dry thoroughly, according to manufacturer's instructions, before use.

Tips & Warnings

• Making a nice bead takes a little practice. Experiment on a piece of cardboard, aiming for an even 1/4-inch to 3/8-inch thickness. Use fresh caulk. If it's too old, it will neither apply well nor last long. Look at the expiration date on the package or test by squeezing a bead on a piece of cardboard. Caulk is fine if the test application looks good and dries in the right amount of time. Tough caulk can be softened for easier removal. Apply caulk remover liquid, wait and proceed. Clean up mistakes and your hands with rubbing alcohol or caulk remover.

• Mold and mildew are inevitable in showers and bathtubs, but are unhealthy. Keep caulking free of both.

Resources

• Caulk remover
• Caulk
• Caulk gun
• Caulk smoother
• Complete caulking kit