Over time, the flexible sealant around your bathroom fixtures can become stained, grimy, and lose its effectiveness. Replacing it periodically is essential for maintaining a waterproof barrier. However, the removal process can be trickier than it appears. If done incorrectly, you risk scratching or otherwise damaging the bathtub, shower enclosure, or basin you are trying to protect.
Here is a guide on how to strip old bathroom sealing compounds safely and effectively.
Removing the Existing Sealing Compound
There are a few methods and tools you can use to lift the old material.
Some people opt to use a utility knife (like a trimming knife or box cutter). While this can be effective, it carries safety risks: you could cut yourself or score the surface of the fixture you are trying to reseal.
If you choose to use a knife, proceed as follows:
- Carefully cut along the length of the flexible joint to separate the silicone from the adjacent surfaces (the wall and the fixture).
- Grab a loose edge and begin peeling the compound away. If you are fortunate, the material will come away in long, easy strips with minimal residue remaining.
For a safer alternative, you can use a specialized sealant removal tool, which is inexpensive and widely available. These tools are designed to scrape off the old compound without posing a risk of damage to the fixture’s surface. They can often be used later to help smooth the newly applied sealant as well.
Using a Chemical Removal Agent
The physical scraping methods described above are affordable and work well, but they require significant manual effort. For an easier option, consider using a sealing compound removal gel or solution. These products are also reasonably priced.
To use a removal gel:
- Load the product’s tube into a caulking gun and snip the tip to the appropriate size.
- Squeeze the gel directly onto the old sealing compound.
- Wait. You should allow the gel to act for at least two hours, but it is often more effective to let it sit for 12 hours or longer, especially if the compound is old and tough.
You can use chemical removers in two ways:
- Apply the gel first and let it break down the silicone, making it much easier to scrape off later.
- Scrape off the bulk of the old compound by hand first, then use the gel to soften and dissolve the stubborn bits that refuse to lift.
Clearing Remaining Residue
If there are still small pieces or smears of silicone left behind, soak an old cloth with a small amount of mineral spirits (or white spirit) and gently rub the remaining residue until it begins to dissolve. The solvent makes the compound less sticky, facilitating easier wiping. If any stubborn pieces remain, you can try picking them off with pliers or tweezers, or scrubbing them away with an old toothbrush.
Once the old compound is completely removed, use the mineral spirits to thoroughly clean the surface underneath. Next, mix a solution of household bleach and water and use it to kill any traces of mold that may have formed.
Thorough cleaning of the area is critical, particularly if you are resealing against tiled walls. Attempting to apply the new flexible compound to an unclean surface can prevent proper adhesion, allowing water to penetrate behind the seal and eventually cause new mold problems.
Allow the surface to dry completely. Once fully dry, you are ready to apply the new compound.
Important Note: If you used a removal gel to strip the old compound, you must wipe down the surface with mineral spirits afterward to remove the gel residue. Any leftover gel will prevent the new sealant from adhering properly.
Applying the New Bathroom Sealing Compound
With the old compound gone, the surface clean, and the area dry, you are prepared for the resealing step. The process is similar regardless of whether you are sealing a bathtub, sink, or shower:
- Insert the compound tube into the caulking gun and cut the nozzle tip. The opening should be approximately the same width as the joint you are filling (the gap between the fixture and the wall).
- Apply the flexible compound smoothly into the gap, wiping away any immediate excess as you go.
- Mix a solution consisting of equal parts dish soap and water.
- Dip your finger into this solution and gently run it along the bead of newly applied compound to smooth it and create a neat, concave finish.
