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Can You Bury Black Gas Pipe? [Explained]

Using a black iron pipe for the gas lines is quite a common scenario.

But what to do when they’re to be installed underground?

You need first to know whether a black gas pipe can be used below the ground.

Can you bury a black gas pipe?

The black gas pipe can be buried underground. But it needs some protective layer to keep it away from rust. Black iron pipes don’t contain any protective coating on them. This is why before burying it you’ve to apply paint over them to protect it from humidity.

That was only a tiny part of our discussion. We’ve explained the whole topic in detail to you. Give it a read if you’re curious to know more.

Let’s get started!

Can Black Gas Pipe Be Used Underground?

Black iron pipes are frequently used in household gas lines. They’re utilized for natural or propane gas. It’s cheaper and more malleable than other iron pipes out there. 

As the name suggests they have a black oxide scale on their exterior. They are heat & water-resistant which makes them an excellent choice for household work. Unlike other iron pipes, black iron pipe for gas lines needs more protection. Because it’s plain and doesn’t contain any protective coatings.

Unless you’re going to wrap it with any protective layer, don’t bury it. It will get affected by rust in a humid environment. The popular solution to protect the metal is painting. The process is similar to painting metal lockers.

How To Install Underground Black Gas Pipe?

We’ve mentioned previously, black gas pipes need extra protection before installing them underground. In this segment, we’ll cover how to bury black gas pipes with proper protection.

Step-1: Cautions To Follow

First and foremost, before working on gas lines, shut off the main gas line. Because even a small spark can lead to accidents and explosions.

When installing a gas pipe, make sure to check with your local authorities. It’s highly important. Because some areas have local codes in place for safety and legal reasons. Also, you’re gonna need a local permit for burying a gas line.

Step-2: Cut The Pipes

Do the measurement check for the black iron pipe first. After that, hold the pipe on a stand and cut it with a pipe cutter. You can use the type of dremel that cuts ductwork as well. 

But use high-quality cutting oil to protect your cutting instruments. If you don’t have any at your hand, these are what we recommend-

Product 1
Product 2

Have you got them? Then let’s move on to the next step.

Step-3: Threading The Pipes

After cutting the pipes, shave down the edges to get rid of the sharpness. Add cutting oil to the edges of the pipes. 

Insert it on a threading dye now. Apply some pressure on the dye while rotating it clockwise. Squirt some more oil into the pipe while rotating. Continue the process until the end side of the pipe flushes with the dye.

Rotate the ratchet in 180 degrees and back off the dye from the pipe. Use a round wire brush to remove any metal shaving of the threaded parts. The pipe is beautifully threaded now. That is how you thread black iron pipes.

Step-4: Attach The Pipes

Use pipe joint compound and Teflon tapes on the threads to connect the pipes. Wrap the Teflon tape clockwise 5 to 6 times around the threads. Once it’s wrapped properly, insert it into the fitting.

If you’re using a pipe joint compound, apply it to the threaded edge. Then insert it into the fitting. It creates a strong seal between the joints. 

Step-5: Check For Leaks

It’s important to check for leaks in the pipes. If you’re wondering if the slow leak can seal itself, the answer is no. You’ve to make sure that there is no leak in the pipe. To check if there’s any leak in the pipe, use an air compressor. 

Run the air compressor from the mainline to run air through the pipe. You don’t want to do this procedure by turning on the gas supply. Because it can be dangerous.

Spray some soapy water onto the joints of the pipe now. Do you see any bubbles forming in the joints? 

If there’s a bubble it means there is a leak in the connection. If not, the joint has no leak.

Step-6: Protections For The Pipe

Now that the pipe is ready to go underground, it needs some protective coatings. Clean the pipe’s surface with acetone first. Apply a coat of rust-inhibitive primer afterward. Let it dry before you apply the second coat to it.

You can now paint the black pipe to protect it from rust. Make sure to apply multiple thin coats of paint to the pipe. Because it’s more effective than applying 2-3 thick coats.

Step-7: Burying The Pipe Underground

Typically, the gas pipe should be buried 18 to 24 inches in depth. But you should always check it with your local authority first. You can bury PEX pipes for this as well.

Make sure the soil around the pipe would be stone or debris-free. Otherwise, it may harm the gas pipe. Also, make sure the pipe is detectable after it’s buried underground.

And with that, we’ve reached the end of our discussion. Hopefully, the steps are clear to you.


Question: What is the difference between black iron pipe and galvanized pipe?

Answer: Galvanized pipes contain zinc coating. It’s more suitable for water supply, expensive, and more durable. Black iron pipes don’t have any protective coatings. They’re cheaper & suitable for gas supply.

Question: How long does black iron pipe last underground?

Answer: Black iron pipes coated with a protective layer, can last more than 10 years. If it doesn’t have any protection it would last less than 10 years.

Question: Can PEX be used for the underground gas lines?

Answer: Yes, you can use Pex for both natural and propane gas lines. Its polyethylene is similar to the plumbing PEX. It’s durable enough to withstand underground pressure.


Hopefully, you’ve gotten your answer to the question: can you bury black gas pipe? We hope this post was informative for you. Anyway, happy working!