Cracked or moldy caulk lets water behind your tub. Fresh caulk looks better and protects the wall.
Difficulty: Moderate. Plan on 1 hr + 24 hr cure.
Safety: Ventilate the bathroom while working.
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Ventilate the bathroom while working.
Cut and scrape out all the old caulk. Get every bit; new caulk won't stick to old.
Clean the joint, wipe it with rubbing alcohol, and let it dry completely.
Run painter's tape on both sides of the joint for a clean line.
Apply a steady bead of 100% silicone, then smooth it with a wet fingertip.
Pull the tape right away and let it cure for the time on the label before using the tub.
Nice work. A new fix shows up every day, and the Fix Ladder has step-by-step guides for common home repairs.