Re-caulking bathtubs, showers and other bathroom fixtures requires special products and techniques for a lasting job.
Ordinary caulks can quickly become mildewed and stained in a high-moisture area such as a bathroom. Improper application or the wrong product can cause the caulk to crack or pull away from joints, allowing water to seep into the wall and causing damage or stains.
When buying caulk for bathrooms, choose a product that is mildew-resistant and specifies that it is for tubs and showers. These special caulks are sold in conventional caulking-gun cartridges, containing about 10 ounces of caulk, and in smaller squeeze tubes.
If you decide to re-caulk, it is best to buy only enough to do the work at hand. Many caulking products have relatively short storage lives after they`ve been opened. A rough guide: 10 ounces of caulk will form a 3/16- inch strip about 50 feet long.
Here are a few tips for the actual caulking job:
When recaulking a tub or fixture, remove as much of the existing sealant as possible, taking care not to scratch fixtures or tiles. A putty knife can usually be safely used to pry and scrape out old caulk; rounding the knife`s sharp corners slightly with a file will make it less likely to cause scratches.
After scraping, use a small brush to remove loose particles from the joint, then clean it with a cloth moistened with alcohol. The alcohol will help remove soap scum that might prevent good adhesion.
Some experts recommend filling a bathtub with water, then getting into the filled tub to caulk a tub-wall joint. The reason is that many tubs sink slightly when filled. If the caulk is applied with the tub empty, sinking can cause cracking of the bead of sealant.
Caulk containers have a plastic nozzle that tapers to a small end. The nozzle is sealed and must be cut with a sharp knife. The size of the strip of caulk that emerges from the container is determined by the diameter of the nozzle at the point where it is cut. The nozzle should be cut at an angle of about 45 degrees.
It is best to have the caulk strip just large enough to seal the joint with one application or pass of the tube. Multiple passes or strips that are too large generally give caulk a lumpy or uneven appearance.
If a caulking gun is used, be sure to understand its operation before starting a project. Caulk is squeezed from most guns by pulling a trigger, but it is also important to know how to quickly stop the flow. With many guns, a toothed rod must be turned to disengage the rod`s teeth from the trigger. Other guns have a lever that stops the flow if pulled.
It is easiest to apply caulk by pulling the tip of the nozzle or tube along the joint, holding it at an angle of about 45 degrees. I recommend practicing a bit on a piece of cardboard or scrap wood before caulking a tub or other fixture. This helps get a feel for the trigger pressure or amount of squeezing needed to get a smooth flow of caulk.
Smooth the caulk immediately, since some caulks skin over quickly and become rubbery. You can use a wet fingertip for smoothing, but the wet tip of a spoon also works well and gives caulk a neat cove shape.
Allow the caulk to dry completely before using your bath or shower.
If you are planning re-caulk your bath or shower area, check out our specially-priced package of products you'll need: