Does Aluminum Boat Rust? The Facts You Need to Know!

Aluminum boats are an excellent choice for boat owners. They are lighter than other boats, they are easy to maintain, and they are long-lasting. However, some boats are subject to corrosion. Are aluminum boats really a risk?

If you’ve ever been on the water, you’ve probably noticed that aluminum boats tend to develop rust after some time. But why does this happen? What causes the boat to rust? We’ll take a look at these questions and more in this blog post.

Does Aluminum Boat Rust?
Does Aluminum Boat Rust?

Does Aluminum Boat Rust?

If you’re a boat owner and an avid boater, then maybe the answer to this question is ‘No!’ You may be surprised at aluminum boats’ seemingly high corrosion levels.

Despite that fact, Aluminium boat corrosion is an actual risk, and you need to be aware of it. Boats are susceptible to corrosion from a number of factors, including the environment, water chemistry, and saltwater exposure.

How Aluminum Boats Rust
How Aluminum Boats Rust

Here’s How Aluminum Boats Rust:

When aluminum hulls come into contact with water or other elements in seawater, they can corrode. Corrosion starts with tiny particles on the metal reacting with water molecules. As this reaction progresses over time, the metal begins to corrode.

The aluminum boat is the anode, and the steel trailer is the cathode. The electrolyte is the waterline, and the oxygen in the water accelerates the corrosion process.

Aluminum Boats Rust Like Other Metals

The process of galvanic corrosion occurs when two dissimilar metals are in contact with each other in the presence of an electrolyte. The electrolyte provides a conductive solution that allows electrons to flow between the two metals, and a chemical reaction takes place that causes the metals to corrode. 

The metal that corrodes the most is known as the anode, and the metal that corrodes the least is known as the cathode. The level of corrosion that takes place is determined by a number of factors, including the type of electrolyte, the pH of the electrolyte, the temperature of the electrolyte, and the relative sizes of the two metals. 

The rate of galvanic corrosion also increases as the difference in electrical potential between the two metals increases.

How Do You Know If Your Boat Is Aluminium? 

Aluminum boats are often identifiable by the color of their hulls. Aluminum hulls are usually a light gray and dull in texture, while steel hulls are relatively shiny. Aluminum also does not stick to a magnet (It is non-magnetic).

How to Spot Aluminium Rust in Your Boat

This form of rust can be tricky to spot, but there are a few things you can look for. The first sign of aluminum rust is often a dry powder on the surface of the metal. If you see this, it’s a good indication that the metal is corroding. 

Another sign of aluminum rust is pitting or crusting on the surface of the metal. If you suspect that your boat has aluminum rust, it’s a good idea to have it inspected by a professional. They can tell you if the rust is severe and what needs to be done to fix it.

How to Inspect Your Boat:

  • Inspect your boat regularly for signs of corrosion, especially in areas where water can collect, such as around fittings and rivets and on the bottom paint or coating. 
  • A sacrificial anode can be installed to help protect against corrosion. This is a metal fitting that is designed to corrode instead of the metal of the boat. 
  • Rivets are often a weak point in a boat’s hull and can be a source of corrosion. Make sure the rivets are tight and free of corrosion. 
  • Check the bottom paint or coating for signs of wear and tear, and make sure it is still in good condition.

Is Your Boat Too Small to be made of Aluminum?

Boats are available in a variety of sizes, but most boat manufacturers now offer models that are semi aluminum. Aluminum is an efficient metal and can be strong and light.

If your boat is too small or lightweight, it’s likely not using an aluminum hull – it will instead use a composite hull (a blend of materials). Composite hulls don’t rust as easily as aluminum hulls.

Does Aluminum Boat Rust - Infographic
Does Aluminum Boat Rust – Infographic

What Causes Aluminium Boat Rust?

Poor Maintenance

Boat owners need to be vigilant about proper inspection and maintenance of their vessels to avoid unnecessary rusting. Neglecting regular maintenance can cause a boat to deteriorate rapidly. 

According to the National Marine Manufacturers Association, neglecting regular maintenance is the number one cause of boat corrosion. echoes this sentiment, stating that “boats that are not properly maintained are more likely to corrode and rust.” 

Boat owners should always inspect their vessels for any signs of rust and take action to correct any problems immediately. Failing to do so can result in significant damage and costly repairs.

Exposure to Salt Water: 

Saltwater and Aluminum may not seem like a compatible mix, but when they come into contact, a galvanic reaction can occur, leading to the oxidation of the aluminum surface. 

This process happens slowly, over a period of time, and it’s accelerated by the presence of an electrical current. The aluminum oxide film that forms on the surface is very thin, but it’s enough to protect the metal from further corrosion. 

If there’s a direct electrical connection between the Aluminum and the saltwater, the oxidation process will be sped up. This is known as electrolysis, and it can cause significant damage to the boat.


As a boat owner, it’s important to be aware of the effects moisture can have on your vessel. In some cases, it can cause the metal to rust, creating a dangerous and costly situation. 

Aluminum boats are particularly susceptible to rusting, as the metal is not as strong as steel and is more prone to corrosion in a marine environment. The Aluminum will form a crust over the metal, which can trap moisture and lead to further rusting.

Poor Ventilation:

Moisture buildup is the number one enemy of aluminum boats. In a marine environment, with all of the salt and moisture in the air, it’s inevitable that your boat will start to rust if the proper precautions aren’t taken. 

One of the biggest problems is that aluminum boats have a bare metal hull. This means that there is no protection from the elements, and any moisture that builds up will cause the metal to corrode. 

The best way to combat this is to make sure that your boat is properly ventilated. If there is good airflow around the hull, the moisture will evaporate and won’t have a chance to cause any damage.

Improper Storage:

It’s happened to all of us: we go out to the garage or storage shed to get our boat, only to find that it’s been eaten away by rust. What could have been a day on the water turns into a day of repairs, and we’re left wondering how it happened in the first place.

The culprit is often improper storage. If boats aren’t stored in a climate-controlled environment, the humidity and moisture in the air can cause them to rust. Even if you live in a dry climate, boats can still rust if they’re not stored properly. 

Boat owners often make the mistake of storing their boats in a marina. While it may be convenient, marinas are often not the best place to store boats. The humidity and salt in the air can cause boats to rust, and the boats can also come into contact with other boats and objects that can damage them.

How to Prevent Aluminium Boat Rust: 

Regular Maintenance: 

Using a boat is a great way to enjoy the water, but it’s important to keep it in good condition to prevent rust. Fortunately, there are a few things you can do to help prevent rust. 

One of the most important things is to regularly maintain your boat. This includes cleaning it and checking for any damage. Make sure to remove any debris or leaves that may have gathered on the boat. 

You should also check the seams and screws to make sure they are tight and not loose.

Prevent Aluminium Rust: Protective Coating
Prevent Aluminium Rust: Protective Coating

Protective Coatings: 

The aluminum hull can quickly corrode and form holes if not protected. One way to protect an aluminum boat is to coat it with zinc or copper-based primer and finish. This will create a durable, corrosion-resistant barrier between the metal and the water. 

Zinc is more effective than copper at protecting aluminum boats from corrosion. Zinc coatings form a thicker barrier and are more durable than copper coatings. Zinc coatings are also less expensive than copper coatings. 

Outboard motors and propellers are particularly susceptible to corrosion. Outboard motors are often made of Aluminum, and the propellers are often made of stainless steel or brass. Zinc coatings can help to prevent corrosion on these parts of the boat.

Proper Boat Storage
Proper Boat Storage

Proper Storage:

 When it comes to boats, special care must be taken to ensure that the vessel remains in good condition. In order to protect your boat from rust, it is important to store it in a dry place and to use a boat lift professional for transportation. 

In addition, it is important to regularly check the boat for any maintenance issues and to address them as soon as possible. 

A permanent solution to this problem is to install aluminum fittings and fasteners, which will help to prevent corrosion due to nonsimilar metals in contact.


There are several steps boat owners can take to improve ventilation and help prevent rust. Firstly, make sure that all hatches, ports, and windows are properly sealed and caulked. 

Secondly, install a good quality ventilation system, such as a forced-air system, which will help remove moisture and excess heat from the boat. 

Finally, keep the boat clean and free of debris, which can also trap moisture and lead to rust and corrosion.

How to Remove Rust from Your Boat

Removing rust from a boat can be a daunting task. There are a few methods that can be used, but it is important to choose the right one for the job. The first step is to grind the spot. This can be done with a grinding tool or a scrubber. 

Be sure to remove all the debris before moving on to the next step. If the rust is severe, a blend of acid solutions may be necessary. After the acid has done its job, use a wire brush to remove any remaining rust. 

Finally, clean the area with aluminum cleaner.

How to Treat Rust

Rust is a common problem for boat owners, and it can be treated with a few simple steps. First, you’ll need to clean the affected area with a spray aluminum cleaning solution. 

Then, apply a coat of epoxy resin to protect the metal. Repeat this process as needed to keep your boat looking its best.

How to Care for Your Aluminium Boat
How to Care for Your Aluminium Boat

How to Care for Your Aluminium Boat

When caring for your aluminum boat, it’s important to understand the different types of corrosion and how to prevent it. Aluminum is a soft and lightweight metal that is prone to corrosion when exposed to salt water or fresh water. 

The main types of corrosion are: 

  • Pitting corrosion: tiny holes that form on the surface of the metal 
  • Galvanic corrosion: when two different types of metal are in contact and form an electric current 
  • Microbial corrosion: when bacteria or other microorganisms eat away at the metal 

To prevent corrosion, it’s important to keep your boat clean and free of dirt and debris. You can also use sacrificial zinc anodes to protect the metal from corrosion. These are small zinc plates that are attached to the boat in areas that are most likely to corrode.

The zinc plates corrode instead of the Aluminum, and this prevents the Aluminum from corroding. Another way to prevent corrosion is to use a protective coating on the metal. 

There are a number of different coatings available, but it’s important to select one that is safe for Aluminum. There are a few different types of coatings that are specifically designed for aluminum boats.

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