Best Way to Clean a Fiberglass Boat Deck – Simple And Easy Steps!

After some fun trips on the water, your white deck is now kind of dirty, with a lot of small embedded dirt stains. That’s not good because a dirty fiberglass deck can get slippery and become dangerous. Not mentioned; it’s not aesthetic.

If you’ve tried many spot removers, but it didn’t work much, in this case, no worries.

Here, you’ll find the best way to clean a fiberglass boat deck using simple steps and the best cleaners. Not only will it revitalize your deck and make it look brand new again, but it will also increase its performance. Read on!

Take Away

Cleaning a fiberglass boat deck is relatively simple. First, you’ll want to wet the deck to remove any loose dirt or debris. After that, apply a deck cleaner or boat soap to help break down any grime or stains. Let the cleaner sit for a few minutes before using a deck brush to scrub the surface. Finally, rinse off the cleaner and dry your boat deck.

Why Clean a Fiberglass Deck Boat

1. The first reason you would want to keep your fiberglass boat deck clean is to keep it in good condition for as long as possible.

2. Since boat decks are often exposed to the elements, over time, they accumulate grime, algae, and mold, making them slippery and unsafe to walk on. So, regularly cleaning your boat deck maximizes safety for yourself and your passengers when boating.

3. Regular boat maintenance helps protect the fiberglass material from potential damage caused by the sun’s harmful UV rays, saltwater, and other factors. 

4. Keeping your boat deck clean is essential to prevent discoloration, chipping, and wear and tear. These issues can significantly impact your boat’s longevity and performance.

5. Maintaining your boat deck clean makes it easier to spot potential issues, such as cracks or dents, that could lead to more significant problems if you neglect them. Detecting the damages in time allows you to handle these issues quickly and avoid costly repairs down the line.

Tools You’ll Need To Clean Your Fiberglass Deck

Tools to clean a fiberglass boat deck

When cleaning your fiberglass boat deck, it’s crucial to gather the right tools and products beforehand. This will make the Cleaning easier and simpler and will save you time and nerve.

Here are some of the essential items you’ll need:

  • Cleaning products: Choose a high-quality fiberglass deck cleaner designed specifically for fiberglass boat decks that use low toxicity ingredients. For example, Star Brite Non-Skid Deck with PTEF Cleaner is highly effective and has elements that minimize environmental damage. 
  • Brush: A long-handled deck brush with soft-to-medium bristles is ideal for reaching difficult areas and preventing scratches on the fiberglass surface.
  • Bucket: You will need a bucket for mixing soap or boat cleaner with water and rinsing the brush during cleaning.
  • Soap: To add cleaning power, you can combine mild dish soap with a dedicated boat cleaner. Just ensure that the soap and cleaner are specifically made for marine environments. This mixture helps break down grease, oil, and dirt, making it easier to rinse away the grime.
  • Non-Skid Deck Cleaner With PTEF: If your deck has stubborn stains, a fiberglass non-skid deck cleaner can help eliminate them and restore the deck’s appearance. PTEF is a synthetic fluoropolymer with non-stick properties that repel water, resist stains, and maintain the glossy finish of the boat’s surface.
  • Pressure washer: (OPTIONAL)This is optional. You can use a pressure washer to help you remove dirt and grime from the deck before and after applying the cleaning solution. If you don’t use a washer pressure, get a hose or a bucket.
  • Polishing: After Cleaning, consider using a polisher designed for fiberglass boats to protect and enhance the gelcoat’s finish.

7 Steps To Clean Fiberglass Deck: The Best Way

Wax a fiberglass boat deck

Before diving into a deep clean, let’s start with simple cleaning steps to remove dirt, grime, and debris from your fiberglass boat deck. 

Step 1. Wet the boat deck using a hose or bucket, and make sure to reach every corner. This will help loosen the dirt and make it easier to remove. If you use a washer pressure, set it on low pressure and maintain a good distance to avoid damaging the fiberglass paint.

Step 2. Once your boat deck is wet, apply gentle soap mixed with warm water on the deck and scrub with a soft-to-medium bristles brush. You can also add some mild soap in a washer pressure and apply it on the deck, but as mentioned previously, make sure to set it on low pressure.

Step 3. Let the mixture of warm water and soap on the deck for 3 to 5 minutes and scrub. 

Step 4. After you’ve scrubbed all the surface of your boat deck, it’s time to rinse it off. Use a hose, a bucket of water, or a washer pressure to thoroughly remove any remaining dirt and the cleaning solution.

Step 5. Finally, let the water run off and use a clean, dry cloth to remove excess water.

Step 6. If the stains still remain after using a non-skid cleaner with PTEF, consider applying a mild acid stain remover for fiberglass. These types of cleaners remove any stubborn stains, as they are extremely strong.

However, if you use an acid stain remover, wear goggles and gloves to protect yourself, and never apply it on paint, galvanized, and varnished surfaces, as it can cause costly damage.

Step 7. (OPTIONAL) Once the deck is completely dry, consider applying a layer of boat wax, depending on your gelcoat’s condition. If your gelcoat isn’t oxidized, you can apply a polymer wax. It will protect and prevent it from getting oxidized and add gloss and luster.

However, if your gel coat is old and worn, you may want to apply a 3M ™ Marine. Many boaters use it on their oxidized gelcoat and say it rejuvenates much of the oxidation without making the surface slippery like wax does. 

Whatever you choose, apply the wax or the 3M ™ Marine in a circular motion, covering the entire surface. After the wax has dried, use a buffer to buff the surface, again using a circular motion. This will bring out the true shine and luster of your deck.

Important note: Before using any stain remover on your fiberglass deck, test it first on a small part of the surface to see if it doesn’t cause any damage. These products contain chemicals and, therefore, are very powerful.

Frequently Asked Questions

Q: Can I use bleach to clean a fiberglass boat deck?

While bleach effectively removes stains and mold from your boat deck, it can also cause damage to the fiberglass surface and harm the environment and your health. Instead of using bleach, consider using a gentle, eco-friendly deck cleaner or an oxygen-based bleach product to help protect the fiberglass and maintain the longevity of your boat deck.

Q: What homemade solutions work well for cleaning boat hulls?

For cleaning boat hulls, a homemade solution of warm water, dish soap, and white vinegar can be effective. Mix 1 gallon of warm water, 1 cup of dish soap, and 1 cup of white vinegar in a bucket. Using a soft brush, scrub the surface of the boat hull, then rinse with fresh water. This solution can be particularly helpful for removing mildew and waterline stains.

Q: Is it safe to use vinegar on a fiberglass boat deck?

Yes, using vinegar on a fiberglass boat can be safe and effective for various cleaning tasks. Vinegar, a mild acid, can help remove mineral deposits, water spots, and mildew without damaging the fiberglass surface. However, it’s crucial to dilute vinegar with water before applying it to your fiberglass boat to prevent potential damage.

Q: What are the best cleansers for fiberglass boat decks?

There are a variety of products available specifically designed for cleaning fiberglass boat decks. Some popular options include boat soaps, non-skid marine-grade deck cleaners, stain removers, and bilge cleaners. Star Brite, 3M Marine, Meguiar’s, and David Instrument are excellent cleaners. A pressure washer can also help remove stubborn stains.

Q: How often should I clean my fiberglass deck boat?

This will depend on various factors, such as how often you use your boat and the weather conditions it’s exposed to. As a rule of thumb, you should rinse the deck with fresh water after every boating trip to remove salt water and other debris. About every 5 to 6 months, do a deep cleaning with deck cleaner followed by a boat wax. Waxing your deck will protect it from the UV and oxidation and give it a nice look.

Q: What are the best eco-friendly cleaners for fiberglass boat decks?

Simple Green, Bio Kleen, Star Brite Sea Safe, Ecover All Purpose, and even soda blended with vinegar.

Final Words!

Cleaning a fiberglass boat is simple if you use the proper method. All you have to do is choose the right cleaner for your needs and follow the steps above, and you are all set! It may not be an easy task unless you use a pressure washer, as it will definitely make the cleaning process easier. However, if you go with the washer pressure path, remember to set it on the lower pressure and keep a reasonable distance. Happy cleaning!

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