How to Fix Galvanized Pipe

Galvanized pipes can be found in much older homes where they are used as water supply lines. These kinds of pipes are not used for gas lines because they contain zinc which flakes off and will end up clogging the supply system. Although galvanized pipes are no longer used in newer homes, they are still used in hand rails and as replacements of existing pipes.

If you have an older home and want to work with galvanized pipes on your own, you need to know everything you can about it. This article will provide the basics on galvanized pipes as well as steps on how to fix one.

The Basics on Galvanized Pipe

Homes that are decades old (about thirty or more) use galvanized pipe extensively. The original purpose for this kind of pipe was to function as a water supply line. A galvanized pipe is basically covered with a layer of zinc to increase its lifespan as well as to prevent corrosion.

There is a tendency for galvanized pipe to react with minerals contained in the water that is carried through it. This leads to the production of scale which then results in lower water pressure. The occurrence of hard water lessens the life expectancy of galvanized pipe.

Other than being used as a water supply line, galvanized pipe can also be used in drains and vents, particularly in older homes. In addition, galvanized nipples are still used to penetrate fire-rated walls for sinks and urinals.

Although galvanized pipe is no longer used in newer home constructions, those who still want to use it are advised to have the PH level of the water in their area checked. Why is that the case? Testing the PH levels allows you to see whether it is appropriate to install a galvanized pipe or not. When the PH levels in your area is low – below 6.5 – then it’s a good reason to use galvanized pipe as that level of PH is hard on copper.

Even if galvanized pipes are no longer common for full, in-home plumbing, they are still pretty common in outdoor applications, particularly on chain link fences or handrails. Why is this so? Galvanized pipe is highly resistant to corrosion which is ideal for use in places where there will be high amounts of exposure to the elements.

Fixing Galvanized Pipe

Although resistant to corrosion, this doesn’t mean galvanized pipe is immune to it. Over time, corrosion will eventually happen and when it does it occurs from the inside out. The best indicator for this happening is when you notice leaks. In fact, the pipe might already be very damaged when you start noticing leaks.

Yes, galvanized pipes aren’t that much popular these days, but a lot of older homes still have this kind of fixture. When you notice a visible leak in your pipe, there’s a good chance that it’s really corroded. Although you can fix the leak, this will only be a temporary solution as the best way to go about this is to replace the pipe entirely.

However, rather than just leave a leak until you can have time to fix it or call for help, why not try fixing it until you have enough time to execute a much more permanent solution? If you don’t know how to fix galvanized pipe, here’s a simple guide to help you out:

1: Estimate The Pipe Split

If the split is rather small, you can repair it with a stainless steel pipe repair clamp. But first, make sure you turn off the water and then open a faucet so that water completely drains from the pipe. After that, use a putty knife to scrape rust and corrosion from the area around the leak.

Slip the clamp around the pipe and make sure that the split is covered by the rubber gasket. Squeeze the clamp close then use an adjustable wrench or nut driver to tighten the nut. After doing this, turn on the water and check for leaks.

2: Replace The Damaged Section

To replace the damaged section of threaded galvanized water pipe, cut the damaged area using a reciprocal saw. Two cuts should be made with one being several inches from the threaded coupling and the other at one of the threads. This should be done at both ends of the section.

Remove the section of the pipe that has been damaged. The next step needs two pipe wrenches so make sure you have them by your side. With one pipe wrench, hold the remaining pipe then remove the coupling with the other.

After doing this, clean the threads then apply thread compound. Make sure you have a female PEX fitting then screw this on and use a wrench to tighten it. Repeat this process for the other end.

Cut a piece of PEX pipe (carefully measured) then crimp them onto the fittings.


Here’s an alternative option of removing the damaged section of pipe:

  • Use a reciprocal saw to cut out the damaged section of pipe.
  • Cut the galvanized pipe back to where there is an existing PVC pipe in the line. Take note that it’s not really necessary to cut near the threads at them.
  • Remove the damaged pipe.
  • Use a rubber coupling to put at the end of each cut.
  • Measure and cut a portion of PVC pipe to fit.
  • Slip the PVC pipe into the couplings to put them in place.
  • Use a wrench or nut driver to tighten the coupling clamps.

Additional Tips

  • Make sure to take off as much galvanized pipe in the plumbing line as possible then replace them with PEX or PVC pipe.
  • A large split is more likely to develop in galvanized pipe compared to a water pipe because it’s not under pressure and as such, can go unnoticed.
  • Heat a coupling that is rusted on with a torch or spray lubricating oil to loosen it.

Again, fixing a galvanized pipe is only a temporary solution because eventually the pipe will continue to erode. But rather than leave leaks unfixed, it’s best to repair a galvanized pipe as a temporary solution until you have time to have the pipe replaced.

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