Caulking the connection between your shower walls and tub prevents leaks and reduces mildew buildup. Removing old caulk and recaulking joints between tiles and your tub is an annual bathroom maintenance job.
If you have tile shower walls, there is a very good possibility that a leak could develop between the tile and the tub. As the house moves (a natural process that occurs in every home), a hairline crack can occur that allows water to get into the joint. Once water gets in, there is no telling how much damage can be done.
There's another good reason to recaulk. If you've tried to remove the black mildew stains from caulk, you know the blemishes are often unbudging. That's because the stains are often behind the caulk — between the caulk and the wall. The answer, of course, is to remove the caulk, kill the mildew, and then replace the caulk.
Removing the caulk isn't as hard as it appears. One company makes a product called Caulk-Be-Gone and another makes an Adhesive & Caulk Remover, two commercial products that can assist you in the job. These products are specially formulated to soften caulk for easy removal.
After the caulk has softened (it may take a few hours), remove it with a plastic putty knife. Clean the joint with paint thinner and wipe the area dry with a clean rag.
Then clean the joint with this famous mildew cleaner:
1. Add 1 quart of liquid chlorine bleach to 3 quarts of warm water.
2. Add 1/3 cup of powdered laundry detergent.
3. Mix thoroughly and place in a spray bottle.
4. Spray the mixture onto the mildewed area. Let it sit until the black mildew turns white. Rinse with fresh water.
Although this mixture is mild, don't forget to wear gloves and eye protection and make sure the area is well ventilated. Make sure the detergent you use is ammonia free. Mixing bleach with a solution containing ammonia can release a dangerous gas harmful to your lungs.
Immediately after eradicating the mildew, use a hair dryer or a hot air gun to thoroughly dry out the area. The joint can now be re-caulked.
Use a roll of blue painter's masking tape for a professional-looking job. Apply the tape to the tub 1/8-inch from the joint. Next, apply another strip of tape along the wall, 1/8-inch from the joint. Now the caulking will go between the two pieces of tape, making straight, smooth lines.
Apply tub and tile caulk into the joint and smooth it with your finger, an old teaspoon, or a caulking spreader. Immediately remove the tape by pulling it out and away from the freshly caulked joint. Be careful not to touch the caulk. Let it dry. You simply won't believe how beautiful your job will look.