How Long Does It Take For A Galvanized Pipe To Rust? (Explained)

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In a perfect environment, a galvanized pipe can last for more than 200 years. But with the presence of chemicals, hot temperature, high humidity, and acidic soil, it can only last between 10 to 75 years. High humidity shortens the lifespan of a galvanized pipe.

pipes stacked in warehouse

Do galvanized pipes rust?

Galvanized pipes rust but it takes years before it corrodes. It can last up to more than 200 years when the environment and other factors are in good condition. It also depends on the coating methods that the steel undergoes as they corrode differently.

The two coating methods include hot-dipped galvanized steel and electroplated galvanized steel.

These methods give different protection for the steel. Electroplated has a thinner coating but has a shiny finish. On the other hand, the hot-dip method has a thick coating yet with a dull gray finish.

The coating matters when it comes to the lifespan of the galvanized pipes. A pipe with a thicker coating can withstand the environmental factors that cause corrosion of the pipes.

This is an important factor to check especially if you plan to lay the pipes outdoor or you plan to use them in an industrial setup.

Reasons galvanized pipes rust

Several environmental factors contribute to the corrosion of the rust. When all these conditions are present, there is a greater chance that the pipes will corrode. But even one factor is present, the lifespan of the pipes still shorten.

When the relative humidity in the environment is above 60%, there is a chance for corrosion. When combined with industrial pollution, wet environment, and increased temperature, it hastens the corrosion.

Acids and alkalis are also contributors. Acid rainwater, acid from hydrogen sulfide, and hydrogen dioxide can corrode a galvanized pipe. It is the same thing with strong alkalis.

Other factors include the presence of moss and lichen, acidic food, acidic drinks, and electrolytic corrosion.

How long does it take for the galvanized pipe to rust?

According to the Journal of Materials in Civil Engineering, it predicted that the galvanized steel zinc layer will be consumed after 211 years upon exposure to the environment with below 60% humidity. However, if it is exposed to an environment with 100% humidity, it will only last for 34 years. On the other hand, if the galvanized steel is kept in a soaked or wet environment, it can only last for 10 years.

With the data published in the journal, it is safe to say that the type of environment plays a big factor that leads to the corrosion of the pipes. You must know the environment type where you live and where you work.

The type of environments includes industrial, tropical marine, temperate marine, suburban and rural.

Environment

Galvanized pipes in an industrial environment are prone to corrosion due to their exposure to airborne chemical compounds such as sulfide and phosphate. The atmospheric contaminants make the environment aggressive corrosive.

On the other hand, the tropical marine environment has high humidity and it is almost corrosive as the industrial type. Pipes nearby the cost are prone to corrosion as the wind contributes to speed up the chemical change of the pipe.

When your pipes are laid out in an industrial and tropical marine environment, expect faster corrosion.

Temperate marine, suburban and rural environments are less corrosive environments – rural being the least corrosive. These environments have lower temperatures, humidity, and chemical composition in the atmosphere. If you lay the pipe in these environments, expect a longer lifespan of the pipes.

Soil condition

Soil is another factor that dictates the lifespan of a galvanized pipe. Less acidic soil is better than the acidic type because it can increase the lifespan of the pipe up to 75 years. In acidic soil, the pipe can only last up to 50 years.

You must also check the aeration of the soil. When there is aeration, it means that there is an indication of oxidized iron. However, if the soil is non-aerated, reduced iron is present.

A well-aerated soil is reddish, yellowish, or brownish while the non-aerated soil is grayish. When laying a pipe, avoid non-aerated soil because it is corrosive to zinc, which is normally the coating of a galvanized pipe.

Water Pipe Burst. Galvanized water pipe is decay

How do I keep my galvanized pipe from rusting?

Even though galvanized pipes do not rust easily, preventive measure is necessary. Maintenance is also a must to keep the galvanized pipe from rusting.

Paints and primers

One of the easiest ways to keep the galvanized pipe from rusting is by using paints and primers. They add a coating to the zinc coating that the pipe already has. Choose a primer perfectly made for metal like a metal self-etching primer.

The primer is additional protection before you apply paint.

Choosing high-quality paint is also important. When choosing paint you must check if it is anti-corrosive, weather-resistant, and abrasion-resistant. As you already know, some galvanized pipes are laid out in an industrial environment. They are exposed to harsh conditions such as extreme weather conditions. You must choose paint that can withstand a harmful environment.

Maintenance

Maintenance plays an important role when dealing with pipes. Without it, you will just wake up one day with rusted pipes. The easiest way to maintain a pipe is through regular checkups.

You must schedule a maintenance check-up with your plumber. But do not rely on the scheduled maintenance.

When you begin to see signs of rust, go to your local hardware store and buy a rust remover.

Cooler temperature

Avoid exposing the pipes to hot temperatures. High temperature hastens the buildup of corrosion.

Although high temperatures do not break down the zinc coating, when humidity and chemicals present in the industrial environment are present, it can lead to corrosion. Keep the environment cool to keep the zinc coating intact.

If possible, try to run cold water in your pipe instead of hot water.

Filter installation

Installing a filter can help to remove toxins or harmful chemicals from your water. It helps to eliminate corrosive substances that can cause rust on the pipe. If you do not have one yet, you can consider adding it to your plumbing setup.

Remove rust right away

Once you spot rust on your pipe, remove it using industrial remover. Removal of rust once you spot it can prevent worsening the condition. This is the reason why you must check your pipes regularly.

There are two common chemicals that an industrial setup uses. These are chemicals with strong alkali or strong acid. However, strong alkali is less effective while the chemical that contains strong acid is caustic. Some industries use electrolysis but it is not advisable for home use.

When cleaning your pipe, avoid cleaners and rust removers that are toxic. Always choose a biodegradable product. Cleaners and rust removers are the cheapest way to wipe out spots of rust present on the pipe.

The top brands for rust removers include Boeshield Rust Free Jug, Evapo-Rust The Original Super Safe Rust Remover, Citrisurf 77 Plus Stainless Steel Cleaner, and Rust Removal, Workshop Hero WH290487 Metal Rescue Rust Remover, and Iron OUT Rust Stain Remover Spray Gel.

Other brands also include CLR Pro and Rust-Oleum Rust Dissolver. The CLR Pro has a fast-acting formula that can break down rust. On the other hand, the Rust-Oleum Rust Dissolver can dissolve the rust within 30 minutes.

Conclusion

Galvanized pipes are a cheaper alternative to copper pipes. It is a perfect material for outdoor plumbing and big construction projects. However, it is prone to corrosion, which can release the chemical lead into the water.

Although it is risky to use, it is economical for large projects, which makes it a better option than copper. With proper maintenance and the right environment, corrosion can be prevented.

Marco
Marco
Meet Marco, a lifelong tinkerer and DIY enthusiast, developed a passion for plumbing after fixing a leaky faucet in his own home. Years later, he turned that passion into a thriving business, Amarco Plumbing, where he shares his knowledge and expertise with the community.