For decades, galvanized pipe was the most popular choice for commercial structures and residential applications alike. But with the recent rise in popularity of PEX piping, can galvanize pipes still withstand years of use in your home? Also, does galvanized pipe rust?
Yes, they can rust, but it takes a longer period. Galvanized water pipes can cause rust and eventually leak. However, the pipes are not prone to rust as quickly because zinc protects the metal for much longer than other metals exposed to the elements.
Galvanized pipes may be suited for indoor use only, such as in a garage, for example. But due to its ability to rust, it is not safe. People could get sick using galvanized pipes for drinking water. In addition to rusting, galvanized water pipes are susceptible to lead corrosion and scale build-up.
Because of this, many homeowners began to seek durable alternatives to them. If you are getting involved in any plumbing work either as a professional or for a DIY task that has to do with pipes, you should consider alternative pipes. Below are reasons you should consider galvanized pipes, with ways to protect and prevent rust.
Contents
What Is A Galvanized Pipe?
Galvanized pipes are made of iron or steel that are coated with a material more resistant to corrosion such as zinc to serve as a protective coating. Zinc is specifically chosen because of its low cost, its abundance, and its slow rate of oxidation. The iron or steel pipes are then dipped into molten zinc.
Without the thin layer of zinc, iron or steel would corrode within a short time on exposure to elements. Thus the use of galvanized water pipes in many homes.
Does Galvanized Pipe Rust?
While it seemed to solve a lot of things in the mid-1900s, much later, it was found that these pipes began to corrode from the inside. This is because the water that passes through the pipes often carries many dissolved minerals that can interact with the inlaid zinc. With time, these minerals remove the zinc coating completely; this is common especially with hard water.
Some of these minerals also get deposited in the pipes so while the outside looks pretty much ok, the insides of the pipes are being damaged. With the zinc coating removed, the iron and steel become exposed and rust very quickly. There were also signs of rust on the outside of these pipes as well from interaction with atmospheric oxygen.
What Is The Life Expectancy Of Galvanized Pipes?
Despite the extended lifespan, they add to the steel or iron pipes, galvanized pipes have a life expectancy of between 25 and 40 years. In areas where the water is hard and it deposits some minerals, the rate of failure may be much faster. After these periods, it is not uncommon to find faults in some parts or the whole plumbing.
How To Identify Galvanized Pipes
If the pipes are new, they often appear as nickel but with age and the environment, they could appear lighter, duller, or could even look darker. You can easily identify whether the pipes in your home are galvanized or not by scratching using a screwdriver. If on scratching, you see a gray color, your pipe is most probably galvanized.
You can use a magnet or the strength of the metal to determine if the underlying metal is iron, steel, or lead. Although they would all reveal a greyish-silver coloration, the lead would scratch very easily, steel would not be attracted to a magnet while iron would attract the magnet.
Problems Of Galvanized Pipes
When the zinc coatings of the pipes corrode, the metal lead could build up in the pipes and be released into the water. Lead is very toxic to humans as it can cause symptoms such as muscle aches, flu, and fever. In worst cases, lead poisoning could cause more serious health conditions such as damage to the mental and nervous systems.
Once the pipes begin to rust, if unchecked, it continues and weakens the pipe and could cause a leak. The rust could also get into the water staining it. Thus it is not uncommon with time to see brownish water running from the taps.
With build-ups, the diameter of the pipes is reduced as is water passage resulting in an eventual decrease in water pressure. On the outside, the rust could eat into the pipes and continue to weaken them, especially at joints creating a fault, rust spots, and leaks.
Rusted Galvanized Pipe Repairs
If the amount of rust on the outside of the pipe is small, you can easily remove it yourself using steel wool and vinegar. While this is a temporary solution to remove the visible rust signs, it does not permanently stop the pipes from rusting again.
For more extensive rusting in the pipe, you might require the hand of an expert. They can do this either by using a mild acid, grinding, or sandblasting. Although in these processes, extra caution is employed so the pipe is not damaged the more.
While it might seem a bit tedious and expensive, a total repiping of the building, if you notice that the plumbing is made of galvanized pipes, works best. Consider replacing these metals with pipes made of more durable materials such as PVC, PEX, or copper. A similar alternative would be to re-work the area that needs attention alone.
Conclusion
Galvanized pipes are pipes coated with a metal of higher resistance to corrosion such as zinc. Before the 1960s, these were prime choices in home plumbing till later when they were discovered to rust and create undesirable conditions.
If you notice brownish water from your plumbing facet or a decrease in water pressure, it might be as a result of rust build-up in the pipe. While the best remedy is the replacement of galvanized pipes with more pipes made of more durable materials, you can make repairs and corrections to the affected sections.
