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How to Clean a Fiberglass Shower in 6 Easy Steps

How to Clean a Fiberglass Shower in 6 Easy Steps

Watermarks, residue buildup, and stains are common issues that fiberglass shower owners encounter.

We’ll show you how to clean fiberglass showers so that you can get yours looking as good as the day you installed them.

How to Clean a Fiberglass Shower in 6 Steps

Woman cleaning a fiberglass shower using a microfiber rag and cleaning products while wearing jeans and a hoodie

Elena Podrezenko/Shutterstock

Cleaning a fiberglass shower involves buying a fiberglass-friendly product or making one yourself.

Then, avoiding abrasive materials, apply the product and let it sit for a while before rinsing and drying it off.

Are you ready to get your fiberglass shower squeaky clean?

Follow the steps below and get ready to pull out your sunglasses afterward—you just may need them after your shower’s makeover.

Step 1: Let the Hot Water Run

Ideally, you should clean your fiberglass right after a household member gets out of the shower. That way, all the grime gets loosened for you.

If you’re the sole member of your household, we understand not waiting to clean your dirty fiberglass after just having cleaned yourself. So, leave your shower running on the hottest setting for about five minutes.

Step 2: Choose a Soft Cloth

With the word “glass” in its name, it makes sense that fiberglass doesn’t hold up well with harsh cleaning tools like coarse brushes and steel wool. In fact, a portion of fiberglass is real glass made from melted sand.

Since desperate times call for desperate measures, we’re here to remind you to use a soft cloth when cleaning your shower.

Step 3: Select a Product and Stick With It

Wet & Forget Weekly Shower Cleaner Spray 64 oz - 2 Pack

Many commercial and make-at-home products exist for cleaning fiberglass showers. While we understand the temptation to mix and match these products in the hope of a better result, the outcome isn’t always desirable.

In fact, mixing certain shower cleaning products can be dangerous, opening the possibility for an explosion if someone lights a cigarette or candle nearby. So, what kinds of products are safe to use on your shower’s fiberglass?

Below are some store-bought products that are great for using individually:

  • Wet & Forget Shower Cleaner
  • Bio-Clean
  • Lime OUT
  • Mr. Clean Magic Eraser

If you prefer a more natural approach, below are some homemade, non-chemical fiberglass shower cleaners you can use:

  • Vinegar, dish soap, and water
  • Rubbing alcohol, hydrogen peroxide, dish soap, liquid Jet Dry, and water
  • Baking soda, a cut piece of citrus fruit, and water

Just as with choosing a non-abrasive cleaning tool, it’s crucial to ensure the ingredients in the store-bought or homemade product you use don’t contain anything that’ll scratch your fiberglass.

Step 4: Let the Product Bond With Your Fiberglass

Every store-bought fiberglass cleaning product will come with its own instructions. We recommend you follow them above everything else stated here. 

However, whether you use a manufactured or homemade cleaner, usually the best option is to let the product mingle with your fiberglass for a while.

So, spray or use a cloth or sponge to apply the product to your fiberglass. Make sure to coat the entire surface with a thin film.

Then, walk your dog, watch that Netflix movie you’ve wanted to see, or check off anything else on your to-do list.

Some products, like Wet & Forget, even recommend leaving their cleaner on overnight.

Step 5: Rinse and Wipe

Once you’ve left your fiberglass shower cleaner on for the recommended amount of time according to the product you used, it’s time to see your work pay off. So, take your shower hose and spray down the fiberglass.

Make sure you don’t leave any product residue behind—you don’t want to undo the work you did! Furthermore, use cold water when rinsing.

That way, the steam won’t build up in your bathroom, which would leave behind the watermarks that you’re all too familiar with.

If you notice any spots on your fiberglass that still have residue remaining, this is an excellent time to spot-treat them with the cleaning product and a little elbow grease.

Once it all looks good, take a squeegee and run it evenly over the fiberglass. Make sure to use even strokes to avoid watermarks from forming.

Finally, grab a microfiber rag and go to town to ensure the fiberglass is dry from top to bottom. Then, enjoy your beautiful fiberglass shower before a household member uses it again.

Step 6: Maintain Your Fiberglass

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We can assure you from experience that it’s a lot easier to maintain fiberglass if you clean it regularly. Not only will your fiberglass look its best more often, but greasy residue won’t have as much chance to build up.

So, how often should you clean your fiberglass? We recommend once per week.

If you’re rolling your eyes thinking that you don’t have time for that, it’s really not bad once you get into the habit, especially if you buy a product that you can spray and leave on overnight after your evening shower. 

On the days when you’re not cleaning your fiberglass, we recommend helping it maintain its mark-free look by using a squeegee.

Simply run the squeegee over the sides of the glass before getting out of your shower. It’s not a perfect solution, but it’ll help reduce the number of watermarks you’ll have to stare at. 

Things to Consider

As you’re getting ready to embark on your fiberglass shower cleaning escapade, below are some must-knows to keep in mind.

  • Bleach can have a devastating effect on fiberglass. If you want to use a product that functions like bleach, use hydrogen peroxide or baking soda instead.
  • Citrus is excellent for tackling stains. You can either cut up a citrus fruit and rub it around your fiberglass or buy a citrus-based cleaning product.
  • Keep your bathroom well-ventilated by opening the windows and doors. Fiberglass cleaning products can have strong fumes that you shouldn’t breathe in large concentrations.
  • If there’s a lot of oil and grease on your fiberglass, mix warm water with white vinegar and spray it on those areas. As a bonus, it helps to remove mildew.
  • Most car windows contain fiberglass. Therefore, it’s safe to use vehicle-oriented cleaners in your shower, as long as the bottle mentions that it’s safe for fiberglass use.

Frequently Asked Questions

Faceless person cleaning a fiberglass shower with pink gloves and a sponge


Do you still have questions about how to clean fiberglass showers? Read on for answers to common inquiries.

What Will Remove Stains From a Fiberglass Shower?

Baking soda, hydrogen peroxide, and citrus are excellent ingredients for removing stains from a fiberglass shower. You can even make a thick paste with baking soda and spread it over the stain.

Whatever product you use, giving it enough time to sit on the stain is crucial. We recommend waiting a minimum of one hour before wiping it off.

How Can You Brighten a Fiberglass Shower?

White vinegar is an excellent option for brightening fiberglass showers. It’s safe to use vinegar on your fiberglass without diluting it, and this will have the highest chance of giving it a brighter appearance.

Baking soda mixed with water is another natural remedy to use as a brightening tool. Furthermore, many shower and vehicle products made for fiberglass advertise that they help with brightening.

How Can I Make My Fiberglass Shower Look New again?

Cleaning your fiberglass shower every week is one of the best ways to get it—and keep it—looking new. Use a cleaning product made for fiberglass and let it sit there for hours or even overnight before rising it.

You can also maintain your fiberglass between cleanings by using a squeegee after bathing. That’ll help reduce the number of watermarks from a hot shower.

What Should You Not Use in a Fiberglass Shower?

You shouldn’t use any material that could scratch your shower’s fiberglass. Items like razors, steel wool, and coarse brushes are fiberglass no-nos.

Bleach is also a terrible product to use on fiberglass. Its strong properties can damage the fiberglass’ outer layer, creating the possibility of far bigger shower issues than some watermarks and residue.

How Do You Clean the Bottom of a Fiberglass Shower?

Cleaning the bottom of a fiberglass shower is similar to how you clean its sides. However, to prevent the cleaning product from seeping out, it’s a good idea to plug the drain while you let the product sit.

It’s crucial to ensure all fiberglass cleaning product residue is down the drain before using your shower again. Otherwise, it can get slippery and cause an injury.

How Do You Tell If a Shower Is Fiberglass or Acrylic?

Fiberglass has a smooth texture and an even white color that gradually fades to yellow if you don’t clean it often enough. It also tends to have thinner edges than acrylic.

In contrast, acrylic tubs have more texture and feel warmer to the touch than fiberglass. It’s a heavier kind of material, and you may notice small dots of other colors within its primary color.

So, How Do You Clean a Fiberglass Shower?

So there you have it—how to clean fiberglass showers.

A fiberglass-approved cleaning product, a squeegee, and a microcloth are the must-have items for cleaning a fiberglass shower.

The good news is that you often don’t need much elbow grease—simply let the product sit before rinsing and drying it for a squeaky-clean look.