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How to Clean the Bottom of a Boat? – 9 Easy Steps

Written by J. Harvey / Fact checked by S. Numbers

how to clean the bottom of a boat

Boaters agree that it is important to clean a boat hull often, but the question is: how do you do it? The purpose of this article is to provide you with relevant information about how to clean the bottom of a boat.

In the end, you will know the step-by-step process of cleaning the bottom of your boat and the tools that you need to perform the job. Moreover, you will also find links to video tutorials about cleaning the bottom of a vessel.

The Best Way to Clean the Boat Hull

Cleaning the hull of a boat is not difficult, but it is not that easy either. To increase your confidence in doing this job yourself, read the steps to clean a boat hull below.

You can wash a boat in the water or clean it on land. However, the best way to do it is to bring the vessel out of the water to make the cleaning process easier.

Aside from it being challenging, cleaning an underwater boat hull also requires more equipment, particularly scuba gear to get to the bottom of a sailboat. You will also need to ensure that the cleaning agent you use is designed to protect the environment.

With that said, below are the steps to clean the bottom of your boat on land.

Step 1: Prepare


You will need cleaning tools and a few other things to clean the hull of your vessel. The cleaning solution you will use should be environmentally friendly and safely interact with wildlife.

  1. Hull cleaning solution
  2. Fresh water
  3. Power washer cleaning machine or water hose
  4. Bucket
  5. Brush
  6. Microfiber cloth
  7. Sponge
  8. Marine polish

Step 2: Take your boat out of the water.


Bring your boat to a spacious and open area where you can freely move to perform the cleaning job. We definitely recommend doing your DIY boat bottom cleaning in the driveway or parking lot.

Step 3: Prepare your tools and cleaning materials.

At this stage you should have already purchased a hull cleaner and the tools that you need. Gather them in one location to ensure that the cleaning process is seamless.

It is important to purchase a cleaning product that is safe for marine life. Common cleaning solutions can interact negatively with the underwater ecosystem.

Step 4: Wash the bottom of your boat with fresh water.


Before applying your cleaning product, wet the hull using a water hose or a pressure washer. You need to take extra precautions when using a pressure washer because it may damage the gelcoat of the hull.

In most cases, 1500 psi is safe for washing your boat’s hull. This pressure level is what most car wash centers use to avoid damage to the coating.

Step 5: Spread the hull cleaner.


Using your cleaning cloth or a microfiber cloth, apply the hull cleaner in all hull areas and let it set for the time provided in the product instructions. The cleaning agent will help loosen the grime and stains on the hull.

If you are still not sure of what to do, check out this post about the best way to clean a boat hull.

Step 6: Brush the underside of the boat and the entire hull.


If necessary, gently brush the hull using a soft bristle cleaning brush to not damage the gelcoat. Scrubbing the heavily stained areas can help loosen the stain and grime quicker.

Step 7: Rinse away the hull cleaner.


Pick up your garden water hose or your pressure water hose and start rinsing away the hull cleaner. Perform a spot check to ensure that all areas are clean.

You can apply the hull cleaner again on areas that are still dirty. Repeat the brushing and rinsing process until you are satisfied with the result.

Step 8: Let the boat dry.

Wipe the water out using your microfiber cloth until the boat is dry. Be careful not to use rough rags or towels that may scratch your boat’s exterior.

If you still need help, here is a video showing how to dry a boat using a boat dry towel.

Step 9: Apply marine polish.


Apply the boat polish when the hull is completely dry. This product can help protect the hull’s gelcoat.

Use your microfiber towel to spread the marine polish in a circular manner. A single coat will do, but you can apply two coats of the polish if you prefer.

Frequently Asked Questions

How often should I clean the bottom of my boat?

To optimize your boat’s performance, most boaters agree that cleaning the hull once a month is ideal to avoid fouling or the accumulation of plant and marine growth. Some boaters perform hull cleaning once every 3 months, but it would be up to which cleaning frequency to follow.

Is pressure washing safe for my boat’s hull?

Using a cleaning machine like the power washer to clean your boat hull is a good option. Setting the pressure level to 1500 PSI will not damage the marine coating of your boat’s hull.

What are the signs of hull damage that require professional attention?

Checking the condition of a boat hull is part of the regular boat maintenance. If your boat hull shows abrasion, soft spot, or a sign of rotting, it is ideal to seek professional help to properly address the damage.

What is the cost to clean the bottom of a boat?

The cost to clean the bottom of a boat is dependent on the size of the boat, the severity of the problem, and the cleaning professional you hire. Cleaning prices of boat cleaning companies can vary depending on your location.

The approximate range per linear foot is $8 to $15.


Having knowledge of how to clean the bottom of a boat is essential for boat owners. By now, you should be capable of performing basic hull maintenance without fouling the growth of marine life that could lead to severe damage.

It is also ideal to apply marine polish on the underside of a boat after cleaning to provide additional hull protection. You can clean the bottom of the boat between one to 3 months.

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