Do Metal Roofs Rust At The Beach?

A family friend recently wanted to build a summer home at the beach. She was rather skeptical about the type of home she wanted to buy because she was unfamiliar with what building materials would last the longest in the salty ocean air. She was worried about the metal areas exposed to the elements. She was worried about if metal roofs rust at the beach?

A metal roof left untreated in a coastal area will rust ten times faster than in normal humidity and salt-free air. Sea air contains salt (an electrolyte) and other electrolytes that oxidize metals. The oxidization, in turn, leads to corrosion. Non-metal roofing options work best at the beach.

I wanted to explore what happens to metal roofs in a coastal area in more detail, so I contacted a few roofing experts. With the information, I got from them, and what I found while doing more research, I found some interesting facts about if metal roofs rust at the beach that I will share in this post.

Do Metal Roofs Rust At The Beach?

Most people know that salt air and metal don’t work well together, but will a metal roof rust in a coastal area? Metal roofs in coastal areas require rigorous and time-consuming maintenance to keep them from rusting.

When a metal roof is left untreated in the salty ocean air, it will rust quickly. Untreated metal roofs will erode ten times faster than metal roofs in normal humidity and salt-free air. Ocean air contains salt, and salt is an electrolyte (great conductor of electricity) and other electrolytes.

These electrolytes are responsible for oxidizing the metal. In turn, the oxidization is what causes the metal to rust. If the metal roof is properly treated and maintained, it will last much longer, but in the long run, choosing a different roofing material would be best.

What Can You Do To Keep Your Metal Roof From Rusting?

You can use a metal roof in coastal areas if you do it right. The maintenance can be costly and time-consuming, but there are a few preventative measures you can take when installing the roof that will cut down on the overall maintenance.

The Type Of Metal You Use Is Vital

If you are determined to install a metal roof or have a metal roof on a home you bought at the beach, then the type of metal you have or choose will determine how fast the roof rusts and how labor-intensive the maintenance will be.

Be careful when using metals like galvanized steel. Galvanized steel works great for non-coastal areas. The metal is dipped in hot zinc to withstand rust and corrosion, so it should work in the ocean air, right?

Not exactly; the zinc is more chemically active than the steel and will react to the electrolytes in the salty ocean air first, thus causing it to rust much quicker in coastal areas than it does inland.

What Type Of Metal Will Work Best In Coastal Areas?

If you are dead set on using metal for the roof of your beach home, you might want to look at aluminum. Aluminum is very resistant to the rust and deterioration caused by the salty sea air. It is a lighter and more pliable metal that outlasts most other metals in coastal areas.

You can add a powder coating to keep the chalky white cast that can accumulate on the roofs at bay. For added protection, you can use specialized rubber paint that resists the effects of the salty air better than other paints.

What Other Type Of Roofing Material Won’t Rust At The Beach?

Luckily, you can use alternative metals that won’t rust as quickly as normal steel or galvanized steel roofing. There is a metal called zincalume; it incorporates zinc, aluminum, and silicone into its protective coating.

The protective coating the manufacturers coat the metal roof with will help your roof to last much longer. The aluminum and silicon elements will protect the zinc and the raw metal underneath from the salty sea spray.

Adding A Waterproof Membrane To Metal Roof In Coastal Area

There are times when the right metal alone won’t protect your metal roof from the salty sea spray, and you need a little more protection to keep your roof from rusting. That is where a waterproof membrane comes in handy.

Most waterproof membranes are made using fiberglass or bitumen. These waterproof membranes will help protect your roof by acting as a barrier between the salty ocean air and the actual roof. It lessens the amount of maintenance you would typically need to do on a metal roof.

An example of a fiberglass waterproof membrane is the Traffigard membrane. It is a quick-drying waterproof membrane that is based on the latest technology. It comes in many different shades of color to suit the needs of most consumers.

Nuraply is a great example of a bituminous coating. These coatings consist of a reinforced polyester layer to give added protection from the harsh ocean air.

By using either of these membranes, you will strengthen your roof’s resistance to the corrosive effects of the windy and salty ocean air.

Pros Of Preventive Steps To Ensure Metal Roofs Won’t Rust

By taking preventive measures such as choosing the right kind of metal, adding a waterproof membrane, and painting the roof with specialized rubber paint created for coastal areas, your metal roof will last much longer.

It will lessen the amount of maintenance you would typically need to do every few months, so you won’t have to worry that the roof will rust or erode. It is also more cost-effective, as you won’t need to spend money on chemicals that help neutralize the electrolytes in the salty air.

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As we know, untreated metal roofs will rust and erode much quicker than the metal roofs that are treated with a waterproof membrane or other preventative treatments.

Using a waterproof membrane will add an extra layer of protection to any metal roof when you need to protect it from the corrosive effects of the salty spray that is common in coastal areas.