Home » Home Improvement » How To Repair a Fiberglass Bathtub – Fix Cracks and Holes

How To Repair a Fiberglass Bathtub – Fix Cracks and Holes

Fiberglass bathtub with a hairline crack in it.

Ever found yourself staring at that unsightly hole in your fiberglass bathtub or shower surround, wondering if there’s a cost-effective solution to fix it? I’ve been down that road before, paying a pretty penny for repairs that I later discovered I could have handled myself. That’s why I’m here to spill the beans on how to repair those pesky holes and cracks in your fiberglass fixtures without the hefty price tag.

Now, I’m no expert, but I’ve learned a thing or two from my DIY escapades, and today, I’m walking you through the process of giving your fiberglass bathtub a new lease on life. With the help of a trusty fiberglass repair kit, a touch of patience, and a sprinkle of elbow grease, you’ll be amazed at what you can achieve. So, grab your tool belt (and maybe a cup of coffee), and let’s dive into the wonderful world of DIY fiberglass repair.

What is Fiberglass and Why is it Used?

When it comes to the world of bathroom fixtures like bathtubs and shower surrounds, fiberglass is the unsung hero. It’s a material that combines the strength of glass fibers with the flexibility of resin, resulting in a durable and versatile composite. Fiberglass is not only lightweight but also remarkably sturdy, making it a popular choice for creating items that need to withstand constant use and exposure to moisture.

The Advantages of Fiberglass for Bathtubs and Shower Surrounds

1. Durability: Fiberglass is tough. It can handle accidental bumps, knocks, and even the occasional dropped shampoo bottle without showing signs of wear and tear. This means your bathtub or shower surround will maintain its pristine appearance for a long time.

2. Water Resistance: One of the most significant advantages of fiberglass in bathroom fixtures is its water resistance. Unlike materials that can warp, crack, or degrade when exposed to water, fiberglass stands strong, forming a reliable barrier against moisture-related issues like mold and water damage.

3. Low Maintenance: Keeping your fiberglass bathtub or shower surround clean is a breeze. A simple wipe-down with a gentle cleanser is usually all it takes to maintain its shine and hygiene. You can check our Best fiberglass shower cleaner guide if you need a commercial cleaner.

4. Customizability: Fiberglass is highly moldable, allowing manufacturers to create a wide range of shapes and designs. This means you can choose a bathtub or shower surround that not only fits your bathroom’s layout but also aligns with your personal style.

5. Aesthetics: Speaking of style, fiberglass fixtures can be finished in various colors and textures, ensuring that your bathroom not only functions well but looks great too.

In a nutshell, fiberglass offers a combination of durability, water resistance, low maintenance, and design flexibility that’s hard to beat. However, even the strongest materials can develop issues over time. That’s where our guide comes in – to help you address those pesky holes and cracks that might appear in your fiberglass bathtub or shower surround. So, let’s roll up our sleeves and get to repair the fiberglass tub.

Necessary Tools and Materials To Fix a Fiberglass Tub

Before you dive into repairing your fiberglass bathtub or shower surround, it’s essential to gather the right tools and materials. Having everything on hand will ensure a smoother repair process and a more successful outcome. Here’s a rundown of what you’ll need:

1. Fiberglass Repair Kit: This kit contains epoxy resin, which is the core component for filling and repairing holes in fiberglass. Look for a repair kit designed specifically for bathtubs and shower surrounds. These kits often include color additives to match your fixture’s color.

2. Sandpaper (Assorted Grits): Sandpaper is crucial for preparing the repair area and achieving a smooth finish. You’ll need various grits, starting from rough (around 60 grit) for initial epoxy shaping, and progressing to finer grits (320 and 600) for a polished surface.

3. Painter’s Tape: Painter’s tape serves two purposes – it helps you create a clean boundary around the repair area, and it prevents the epoxy from spreading beyond the intended spot.

4. Ziplock Bags (Cut into Sheets): These sheets are used to smooth out epoxy during the repair process, ensuring an even and level surface.

5. Toothpicks: Toothpicks are handy for precisely applying epoxy into small holes and crevices.

6. Plastic Sheets: These sheets are used to cover the epoxy-filled holes, allowing you to tap out air bubbles and create a smooth surface.

With these tools and materials at your disposal, you’ll be well-equipped to tackle your fiberglass repair project. Each item serves a specific purpose, from mixing and applying epoxy to sanding and achieving a flawless finish. As you’ll soon see, a little patience and the right tools can work wonders in restoring your fiberglass bathtub or shower surround to its former glory. Now that you’re armed with the essentials, let’s move on to the step-by-step repair process.

The Fiberglass Tub Repair Process

Repairing the fiberglass tub with the steps presented in the article.

Now that you’re equipped with the necessary tools and materials, let’s dive into the step-by-step process of repairing holes in fiberglass surfaces using a repair kit. We’ll guide you through each stage, from mixing the epoxy to achieving a smooth, seamless finish.

Step 1: Prep and Tape

Begin by prepping the area around the holes you intend to repair. Use painter’s tape to create a clean boundary around each hole. This not only contains epoxy but also helps with sanding later on. Ensure the surface is clean and free from any debris or oils.

Step 2: Mix the Epoxy

Your fiberglass repair kit will likely include epoxy resin and a hardener. Follow the manufacturer’s instructions for mixing the two components. Thoroughly combine them until you have a uniform mixture. This is where the toothpicks come in handy – use them to mix the epoxy for around 45 seconds.

Step 3: Fill the Holes or Cracks

With the epoxy mixed, it’s time to start filling the holes. Use toothpicks to apply the epoxy directly into the holes. If the holes are larger, your repair kit might include fiber mesh to provide additional strength. Allow the epoxy to slightly overfill the holes.

Step 4: Brush Extra Epoxy

Now, use a brush to spread and build up the epoxy on the holes. Don’t worry about the appearance at this stage; the next step will refine the surface. Your goal here is to create a slightly elevated surface to accommodate sanding.

Step 5: Tap Out Air Bubbles

Lay plastic sheets over the epoxy-filled holes. Gently tap over the plastic using a tool like a mallet or a soft-faced hammer. This step helps eliminate air bubbles and ensures a smoother surface. Allow the epoxy to cure for the recommended time before moving on.

Step 6: Sanding

Once the epoxy has cured, remove the plastic sheets. Begin sanding the repaired areas using rough sandpaper (around 60 grit) to level the surface and remove excess epoxy. Gradually switch to finer grits (320 and 600) for a polished finish. Keep the surface wet with water to achieve the smoothest result.

Step 7: Final Touches

After sanding, your repair should seamlessly blend with the surrounding fiberglass. If needed, touch up the repaired area with paint or a gel coat to match the color. This step might not be necessary if your repair kit already includes color additives.

Step 8: Enjoy the Results

Congratulations! You’ve successfully repaired holes in your fiberglass bathtub or shower surround. Not only have you saved time and money, but you’ve also gained the satisfaction of restoring your fixture to its former beauty.

Remember, while the repair process might seem intricate, it’s entirely manageable with patience and attention to detail. Commercial repair kits, such as the Devcon Fiberglass Repair Kit, offer comprehensive solutions that simplify the process, making it accessible to both beginners and experienced DIY enthusiasts. With the repair completed, you can now enjoy a watertight and visually appealing surface that’s ready for many more years of use.

Sanding and Finishing the Holes and Cracks

Sanding and finishing are crucial steps in achieving a seamless and polished repair on your fiberglass bathtub or shower surround. Let’s walk through the process to ensure your repair blends seamlessly with the rest of the surface.

Step 1: Remove the Plastic Sheet and Initial Sanding

Begin by gently removing the plastic sheet that was placed over the epoxy-filled holes during the curing process. You’ll notice that the epoxy has now hardened and taken the shape of the repair area. Before proceeding with sanding, take a moment to assess the surface and ensure it’s ready for the next steps.

Step 2: Sanding with Different Grits

Sanding is where the magic happens, refining the repaired area to create a surface that looks and feels like the rest of the fiberglass. Start with rough sandpaper, typically around 60 grit. This coarser sandpaper will help you remove excess epoxy and level the surface. Carefully sand the repaired area, maintaining an even pressure.

As you progress, switch to finer grits of sandpaper. Move on to 320 grit, then ultimately to 600 grit. Each increase in grit size helps to further smoothen the surface and eliminate any visible imperfections left by the coarser sandpaper. Remember, the goal is to achieve a flawless finish that seamlessly blends with the surrounding fiberglass.

Step 3: Utilize Water for Optimal Results

Here’s a pro tip that can make a significant difference in the quality of your finished repair: use water while sanding. Keeping the surface damp with water while sanding serves multiple purposes. Firstly, it prevents the sandpaper from clogging up with epoxy residue, ensuring a more effective sanding process. Secondly, it helps to reduce friction and heat generated during sanding, preventing any potential damage to the fiberglass.

By maintaining a wet surface, you’ll experience smoother sanding and achieve a more refined finish. As you progress through the grits of sandpaper, continue to keep the surface wet. This simple technique can lead to a remarkably polished outcome.

Step 4: Inspect and Appreciate

Once you’ve completed the sanding process, take a moment to inspect your repair work. Run your fingers over the repaired area to ensure it feels smooth and even. Check for any visible imperfections or uneven spots. If needed, you can repeat the sanding process with finer grits until you achieve the desired level of smoothness.

With the sanding complete, stand back and admire your handiwork. You’ve successfully navigated the sanding and finishing stages, transforming a repair area into a flawless part of the fiberglass surface. The final result is a bathtub or shower surround that not only looks as good as new but also stands up to the test of time.

Remember, sanding and finishing are stages that require patience and attention to detail. Taking your time during these steps will ensure that your repair seamlessly integrates with the existing fiberglass, leaving you with a finished product that’s both functional and visually appealing.

Final Touches and Results

The end result of repairing the fiberglass tub.

Congratulations! You’re nearing the end of your journey to restore your fiberglass bathtub or shower surround to its former glory. In this section, we’ll cover the final touches that bring your repair project to a satisfying conclusion.

Step 1: Removing the Painter’s Tape and Final Sanding

As the repair nears completion, it’s time to remove the painter’s tape that has been protecting the surrounding area. Gently peel off the tape, revealing the repaired surface underneath. The edges of the repair area should now be crisp and well-defined, thanks to the careful application of painter’s tape.

With the tape removed, it’s time for one last round of sanding. This time, use the finest grit sandpaper available, such as 600 grit. Sand the repaired area once again, ensuring that it’s perfectly smooth and free from any imperfections. This final sanding pass contributes to the impeccable finish you’re aiming for.

Step 2: Admiring Your Handiwork

As you complete the sanding process, take a moment to appreciate the transformation that has taken place. The holes or damage that once marred the appearance of your fiberglass surface have now been expertly repaired, leaving behind a flawlessly smooth and flush area.

The results of your efforts speak for themselves – a bathtub or shower surround that boasts a repair that’s virtually undetectable to the eye. The repaired area seamlessly blends with the surrounding fiberglass, creating an aesthetic that’s both pleasing and professional.

Step 3: Options for Finishing

With the repair complete, you have a few options for finishing touches to consider:

  1. Natural Finish: If you’re content with the color and appearance of your repaired fiberglass surface, you can choose to leave it as is. The smooth, flawless finish achieved through the repair process can be a testament to your DIY skills and attention to detail.
  2. Paint or Cover: In cases where the repaired area is particularly large or visible, you might consider painting or covering it to match the surrounding surface. Some repair kits even come with color-matching options, making it easier to achieve seamless integration. Be sure to follow manufacturer guidelines if you decide to paint or cover the repaired area.
  3. Maintenance: Remember that maintaining your repaired fiberglass surface is crucial to its longevity. Regular cleaning and proper care will ensure that the repaired area continues to look its best for years to come.

Step 4: Revel in Your Accomplishment

As you stand back and admire your handiwork, you’ll feel a sense of accomplishment that comes from successfully tackling a home repair project. Repairing holes in fiberglass is no small feat, and your dedication has paid off in the form of a bathtub or shower surround that’s both functional and visually appealing.

Whether it was a small screw hole or a more substantial repair, your ability to follow the step-by-step process and pay attention to the finer details has led to remarkable results. You’ve not only saved money by avoiding costly replacements but also gained valuable DIY skills that you can carry forward to future projects.

So, take a moment to bask in your accomplishment. You’ve successfully learned how to repair holes in a fiberglass bathtub or shower surround, and the seamless finish is a testament to your hard work and determination.

Additional Tips for Patching a Fiberglass Tub

Repairing holes in a fiberglass bathtub or shower surround is a skill that can be incredibly useful for maintaining the integrity and appearance of your bathroom fixtures. In this section, we’ll explore some additional tips and considerations to help you tackle more complex repairs and extend your newfound expertise to other fiberglass-related projects.

Addressing Larger Holes with Fiber Mesh

While the repair process outlined in this guide is perfect for small holes and damages, larger holes may require some additional reinforcement. Some repair kits include fiber mesh, which provides extra strength to the repaired area. If you’re dealing with a hole that’s larger in size, follow the manufacturer’s instructions on using the fiber mesh to ensure a secure and lasting repair.

Handling Cracks and Minor Damages

The repair kit you’ve used for filling holes can also be a valuable ally in addressing minor cracks and damages in your fiberglass surfaces. Whether it’s a hairline crack or a small chip, the epoxy in the repair kit can be applied to provide a seamless fix. Just follow the same steps you’ve learned in this guide, adapting them to the scale of the repair needed. The end result will be a surface that’s as good as new.

Expanding Your DIY Horizons

Now that you’ve successfully repaired holes in your fiberglass bathtub or shower surround, you may be wondering if the skills you’ve acquired can be applied elsewhere. The answer is a resounding yes! The same repair techniques can be employed for various other fiberglass repairs around your home.

From repairing fiberglass fixtures like sinks and countertops to addressing damages on boats or automotive parts, epoxy repair kits offer a versatile solution for a wide range of projects. Always remember to adapt the process to suit the specific requirements of each repair, and you’ll find yourself equipped to handle fiberglass repairs in numerous contexts.

Bathtub Crack Repair FAQ

Can fiberglass bathtubs be repaired?

Yes, fiberglass bathtubs can be repaired using epoxy repair kits specifically designed for fiberglass surfaces. These kits allow you to fill holes, fix cracks, and address other minor damages. While small repairs can be done by individuals with basic DIY skills, more extensive repairs may require professional assistance.

How to repair fiberglass tub scratches?

Repairing fiberglass tub scratches can be achieved using the same epoxy repair kit. Apply the epoxy over the scratched area, ensuring it’s properly mixed and evenly spread. Sand down the repaired area to achieve a smooth finish that matches the rest of the tub’s surface.

How to fix a fiberglass tub chip?

Repairing a fiberglass tub chip involves using epoxy to fill the chip and create a seamless surface. Following the steps outlined in this guide for filling holes can also be applied to fixing chips. The goal is to apply the epoxy evenly, sand it down for a smooth finish, and achieve a repair that blends in with the surrounding surface.

How to repair a fiberglass tub surround?

Repairing a fiberglass tub surround follows a similar process to repairing a fiberglass tub. You can use an epoxy repair kit to fill holes, cracks, or chips in the surround. The key is to follow the steps carefully, ensuring proper bonding and a smooth finish.

How to fix a squeaky fiberglass tub?

If your fiberglass tub is squeaky, the issue might be related to the tub’s installation or the supporting structure underneath. Repairing squeaks might involve adding support, tightening any loose components, or addressing the installation. In some cases, it’s recommended to consult a professional to diagnose and fix the underlying cause of the squeak.

What do I need to repair a fiberglass tub?

To repair a fiberglass tub, you’ll need a fiberglass repair kit that includes epoxy, sandpaper of various grits, painter’s tape, toothpicks, and plastic sheets. These tools and materials will allow you to fill holes, fix cracks, and achieve a smooth finish.

Can you repair a cracked fiberglass tub?

Yes, you can repair a cracked fiberglass tub using epoxy repair kits specifically designed for fiberglass surfaces. The epoxy will bond to the fiberglass, sealing the crack and restoring the tub’s integrity. However, the size and severity of the crack may determine whether you can effectively repair it yourself or if you should seek professional help.

Who can repair a fiberglass tub?

Repairing a fiberglass tub is a task that can be undertaken by individuals with basic DIY skills. Following instructions, using the right tools, and taking your time will help you achieve successful results. If you’re unsure or uncomfortable with the repair process, it’s always a good idea to consult a professional for assistance.


Repairing holes in a fiberglass bathtub or shower surround might have initially seemed like a daunting task, but with the right tools, materials, and guidance, you’ve successfully navigated the process. By following the step-by-step instructions outlined in this guide and incorporating the additional tips and considerations, you’ve gained the confidence and skills to take on more DIY projects in the future.

As you continue to explore the world of home repairs, keep in mind that every project is an opportunity to learn, grow, and enhance your living space. By approaching repairs with the same enthusiasm and determination you’ve demonstrated here, you’ll be well-equipped to tackle a wide array of challenges and make your home a more comfortable, functional, and beautiful place.

Last Updated on August 14, 2023

Leave a Comment