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How To Remove Silicone Caulk From Fiberglass Shower Stall

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Silicone caulk is a sticky gel that works well to seal various materials, including plastic, glass, metal, and wood. Using silicone in a shower stall is beneficial for many reasons. First, water won’t leak out of the shower stall’s cracks and holes thanks to silicone and waterproof sealant capabilities.

It resists mildew and can lengthen the lifespan of your shower stall. But eventually, you’ll need to take the silicon caulk off your shower stalls edges and replace it.

To go about this, there are several ways you can give your shower stall a thorough cleaning, be it a separate shower or one over an acrylic bathtub. In our guide, rather than using a commercial caulk remover you need to purchase, you can use simple at-home methods for removing silicone caulk from fiberglass.

By the end, you’ll have the easiest ways to remove the old silicone caulk using our many caulk removers. Clean the area and fill gaps with new silicone caulking for a fresh watertight seal from your caulk gun and angled tip. (Learn How Long Should Mastic Dry Before Grouting)

Ways To Remove Silicone Caulk

Why Remove Caulk From Fiberglass Shower Stall?

  1. The likelihood of mildew developing behind the new caulk will be eliminated by removing the old caulk.
  2. Old caulk has not yet bonded to the surface, making it simpler to remove than to re-glaze.
  3. After removing the remaining caulk, you can apply the new caulking on a good surface.
  4. When it comes time to re-glaze, many people choose to remove and discard the silicone caulking before cleaning and to do so. Unfortunately, this is a terrible use of caulk.
  5. Use a plastic putty knife, utility knife, or razor blade to remove silicone caulk quickly. Remove excess caulk and clean with acetone; put the new silicone caulks on, and you’re ready.
  6. Any rust stains will be removed when removing silicone from fiberglass shower stall or tub.
  7. Because there are no gaps or other flaws in the existing caulk, re-glazing is made simpler by removing it.

Household Items That Remove Silicone Sealant From Fiberglass Shower Stall

Here are some of the best ways for removing silicone caulk using items around the home rather than purchasing an expensive chemical caulk remover.

1. Acetone

Nail polish remover and other household items contain acetone. It can dissolve silicone caulk but may damage surrounding materials. To remove silicone from fiberglass with acetone, mask off the caulking area.

You can remove silicone from fiberglass panels with a metal utility knife, scraper, or razor blade. This method works well, but it’s not recommended if you have acetone-sensitive bathroom materials. (Learn How Long Before Putting Appliances On New Tile)

2. Baking Soda

Use baking soda to remove silicone caulk from fiberglass. Baking soda’s sodium bicarbonate reacts with vinegar to dissolve silicone quickly.

Apply dish soap to the caulked area and let it sit for a few minutes. After that, mix baking soda with dish soap and use a scrub brush or toothbrush.

Razor Blade Remove Silicone Sealant

3. Razor Blade

With a razor blade, carefully start scraping off the caulking from the fiberglass panel. This can be used with other methods to get caulk off a flat surface without scratches.

4. Boiling Water

Boiling water is among the best ways how to remove silicone caulk from fiberglass shower stalls. Wet a cloth with boiling water and place it on the caulked area for 10 minutes. After heating the surface, use a metal scraper or razor blade to remove the caulk.

5. Hairspray

Hair spray can remove silicone caulk. This method is easier than others, but hairspray contains flammable chemicals. So instead, spray hairspray around the caulked area and wait.

After a while, you should be able to easily scrape caulk off fiberglass panels with a metal scraper or razor blade.

6. Lighter Fluid & Acetone

Mix acetone and lighter fluid to remove silicone from fiberglass. Be careful when mixing acetone with other chemicals, as it can ignite.

Apply the mixture to the caulked area. Wait a few minutes, then scrape off any leftovers. Clean the area around your shower stalls with rubbing alcohol before applying the new caulking.

7. Mineral Spirits or Lacquer Thinner

Mineral spirits and thinners can remove silicone caulk from fiberglass. It’ll dissolve caulk and remove any grime. Next, apply mineral spirits to the caulked area and wait 10 minutes.

Afterward, use a metal utility knife or razor blade to remove the caulk from fiberglass surfaces carefully. Wash down with warm water, then rubbing alcohol to get rid of the oily residue.

Precautions and Safety

  • Most silicone materials can be dissolved using the oil-free solvent acetone or acetonitrile without harming the glass fiber.
  • Most silicone materials dissolve in mineral spirits without harming the fiberglass. However, it frequently leaves a greasy film on the surface that needs to be removed with dishwashing soap or a cleaner.
  • Never use kerosene, gasoline, or any other solvent derived from petroleum. These solvents are highly flammable and might not be safe to use close to an open flame.
  • Never blend solvents by mixing them. Several chemical types can be found in some silicone removers. For example, combining different solvents might create a stronger solvent that harms fiberglass.
  • Use silicone remover sparingly because it damages the manufacturing-used mold release agents and causes the use of new mold release before painting or applying adhesive to treated surfaces.
  • Put on old clothes, protective gloves, and eye protection when you use the above methods to remove silicone caulk.
  • To ensure that the silicone remover won’t harm the non-porous finish on the glass fiber surface, test a small, concealed area first.

Using Heat To Remove Silicone Caulk

The simplest method is using a hairdryer to remove silicone caulk from a fiberglass shower stall or acrylic bathtub. You only need to keep a distance of 8 to 11 inches from the surface for 40 to 60 seconds.

Keep the hairdryer set high, and you can scrape using a razor blade. Here are the full steps for using your hair dryer to remove silicone caulking. (Learn How High Should A Tub Spout Be)

Remove Silicone With Hair Dryer

  1. If you have one, you can use a hair dryer to remove the silicone caulk from your fiberglass shower stall.
  2. Put the hair dryer on high heat and place it next to the silicone caulk.
  3. The caulk should soften and become pliable as you watch.
  4. You can scrape the caulk when it softens with a putty knife or another sharp object.
  5. To avoid scratching the surface, scrape against the fiberglass grain.
  6. Before using a hair dryer to remove silicone, you should know a few things.
  7. Make sure the area you’re working in is first adequately ventilated. When silicone is heated, it can release dangerous fumes, so it’s crucial to work in a well-ventilated space.
  8. Always wear gloves when working silicone. Protecting your hands is essential because it’s difficult to remove once silicone has dried on your skin.
  9. Third, set your hair dryer to the lowest setting. The silicone shouldn’t be overheated because that could make more harmful fumes come out of it. Before peeling off the silicone, and other materials, heat it briefly.
  10. Fourth, proceed cautiously and slowly. When removing silicone, it’s crucial to take your time to avoid harming the surface underneath.

Removing Silicone Without Chemicals

If you don’t want to use chemicals, there’s another method you can try. Sometimes, boiling water to loosen old silicone caulking makes removing it easier.

Start by boiling a pot of water on the stove. Once the water is boiling, carefully pour it over the caulking you want to remove. Try to avoid getting the surrounding areas wet.

Let the boiling water sit for several minutes, then use a putty knife or your fingers to pull away the caulking. If any residue remains, you can repeat this process.

Heat Gun To Remove Silicone Caulk

Using Heat Gun To Remove Old Silicone Sealant

A heat gun is the best tool to remove silicone sealant from a surface. Heat guns are inexpensive, simple to find, and operate on the same theory as a hair dryer.

The silicone will soften and become pliable when the heat gun is pointed at it. Then, using a putty knife or another sharp object, you can scrape it off.

You might need to use a chemical solvent or more heat if the silicone is resistant. Use caution when working with chemicals because they can harm surfaces.

Always perform a small-scale test and then adhere to the manufacturer’s recommendations. To prevent burns when using a heat gun, use it in a well-ventilated area and wear protective gloves. (Learn How Long Can Tar Paper Be Exposed)

Removing Silicone With A Scraper

A few straightforward tools will remove silicone caulk from a fiberglass shower stall. You will need a scraper to start. For this, a razor blade or a putty knife can be used.

Start by moistening the area with warm water, and then use the scraper to scrape the silicone.

Put the scraper carefully underneath the silicone caulk and start prying it up. Work slowly and take care not to scratch the shower stall’s surface. Use a vinegar solution to remove any leftover silicone caulk after you’ve mostly removed it.

Combine vinegar and water in equal amounts in a bowl, then sponge the mixture onto the affected area. Next, gently scrub the area until all the residue has been removed. Afterward, you can wipe away any leftover material with a cloth or paper towel.

Prevent Mold And Mildew Growth

Before applying the new caulk, ensure the area is thoroughly removed after removing all the old silicone caulking. If mold or mildew is not removed, it could quickly reappear and not adhere properly.

Start removing old caulking with a putty knife or your fingers before cleaning the area. Next, clean the area with a damp cloth. You can also use a mild cleaning solution.

Before applying the new caulking, ensure the area is completely dry after cleaning. If not, the new caulk might not stick properly or grow mold or mildew.

How To Remove Silicone Caulk From Fiberglass Shower Stall