Pipe thread sealant is any material that is used to help tighten the bond between manually or mechanically connected pipe components. Anytime you need an air-tight or water-tight seal between threaded pipe units, a thread sealant is the way to go.
Thread sealant can take the form of a special kind of sticky tape that can be carefully wound around the threading, or a soft compound that can be brushed on like paint.
Why Do You Need Sealant?
Pipe components for natural gas lines have threaded or ribbed male and female components that simply screw together. These two pipe components form a connection that is sealed to the naked eye, but which is still loose enough to allow natural gas to leak out, and cause a dangerous build-up of combustible vapor.
The thread sealant simply bonds with the male threading to create a stronger seal when the female section is screwed in. This layer prevents the natural gas from leaking out through invisible imperfections in the piping and can help keep your family safe.
Various factors can also cause the metal of your piping to subtly expand or contract, such as changes in ambient temperature, and vibrations absorbed by the metal pipes. These factors can loosen the manual bond between threaded components, and the sealant helps protect against leakage due to these factors.
Let’s take a look at the different kinds of thread sealant that you can use and the benefits that each offers.
Thread Sealant Tape
Thread sealant tape is a simple adhesive strip that can be applied to the male threaded pipe to thicken the threading and make the bond with the female pipe tighter.
What should you know first? Firstly, it’s important to get the right tape for the job. Thread sealant tape is a special sub-category of adhesive strips meant to be flexible, tough, and durable thanks to the important job it does. Don’t try to substitute a “home remedy” alternative to sealant tape. Make sure that the product you choose is specifically categorized as “sealant tape” or “plumbers’ tape”.
Secondly, make sure that your thread sealant tape is the correct width and variety for the job. A small diameter pipe will take ½” wide tape, and a larger pipe would do better with ¾” to 1” thick tape. Get a low-density tape to ensure maximum compaction and a tighter seal.
Begin your taping job with a taught section of tape, and wrap it tightly, clockwise to the direction that you see when the pipe is facing you, around the male metal threading component. Failing to secure the tape in this configuration can actually cause the tape to bunch or shred once you screw on the female component.
Start at the top of the threading, and overlap every half-tape width as you go. Two or three passes from top-bottom-top should be enough to create a good, strong seal that won’t interfere with the hardware while still being air-tight.
Once you’re done taping, just give the tape a solid yank or cut with scissors to free the reel. Carefully press down the loose tab and screw the pipe into its female component for a nice, strong seal that can withstand temperature changes, vibrations, and most normal pressure fluctuations.
Your tape layer should be thin and flexible enough to keep the threading workable and allow an easy and mess-free screw-on.
Pipe Joint Compound
The second option available to you is a pipe joint compound. This is a sliver, glue-like substance that typically comes in a can, and is brushed onto the male pipe threading with the accompanying brush that is often attached to the can’s lid.
To apply, first make sure that the male and female threads are clean of any oil, dirt, or debris to ensure a tight, clean seal. Use the brush component of the lid to stir the compound and render it more uniform and usable. Gently brush on a thin layer of the joint compound, making sure to “paint” only the treading, and not the base of the joint.
As you screw in the male and female threaded pipes, the joint compound will begin to clump up a bit towards the top of the male threading, and you may need to use a wrench to give one or two extra turns. Don’t overdo it, though, as too much tightening can compromise the effectiveness of the compound.
Now, let your compound dry. This shouldn’t take more than 15 minutes, and your gas line will be ready for use.
Which is Better?
While both sealant tape and joint compound can do an excellent job on a gas line, the joint compound has a reputation for being a bit more durable and permanent.
Pipe compound is a bit thicker and gloopier, and tends to create a better seal for vapors and gasses, whereas many homeowners prefer tape for water-bearing piping. But so long as your threading is sealed, your gas line piping will be safe and leak-free. The quality of the product makes a big difference, too, so don’t be afraid to spend a little more for a better-sealing item.
Some states may actually require joint compounds to be used for gas line sealing, so make sure to check your local laws and use the appropriate material.
Is Pipe Thread Sealant Permanent?
When done correctly, both thread sealant tape and joint compound can last for years. While sealant tape is generally durable, it might not be a bad idea to replace thread sealant tape every five years, to be absolutely sure that the material is fresh and not degrading.
While the lack of exposure to air and moisture should beep the tape relatively safe, it’s not a bad idea to replace sealant tape every five years to be on the careful side.
Turn off your natural gas first before doing any replacement work. Gently peel off the tape that will come off readily, and use a needle to carefully remove the remaining tape from the grooves of the threading, and pull them away from the threading as they come loose.
A joint compound should last for quite a few years, if not decades, and does not generally need to be replaced.
Can You Use Both?
Yes, it is possible to use both sealant tape and joint compound on a gas line! Simply do a single careful wrap-around with your sealant tape, add a layer of joint compound on top of this, and screw in the components.
This will provide you with an even stronger bond, and the two sealant elements will do double time to protect against gas leaks and hold up well seasonally. This is especially useful when working with natural gas, and helps provide a barrier that is both stable and capable of gently expanding and contracting with temperature changes.
Things to Avoid
Don’t use plumber’s putty as a replacement for a joint compound. The two materials are not the same and are not equally tough, long-lasting, or safe to use on gas piping. Remember, you want to prevent dangerous gas from leaking out into your home. This is not the time to cut corners or find cheap substitutes.
You must absolutely make sure that your gas has been turned off before making any of these repairs. This is crucial, and failing to adhere to this step could cost you dearly. Please always turn off natural gas in your home before replacing or repairing thread sealant in your natural gas pipes.
You’re also going to want to make sure that your gas line piping is clean, dry, and free of debris or dust before the sealant job is started. This will help ensure that the sealant is applied with absolutely no gaps and no room for leakage to occur.
Make sure that you are using quality materials that have not outlived their maximum strength. For example, most sealant tapes are good up to three years beyond manufacturing, and most joint compounds are good for eight months after the manufacture date. Please check all labeling for dates and “best by” dates, and replace any expired or worn materials with new products.
Pipe thread sealant for gas lines can take the form of either sealant tape or joint compound. The sealant tape is wound two to three times around the male threading in a clockwise direction, and the joint sealant is carefully brushed on over the threading. You can also use both for an even stronger seal.
This sealant is necessary to help prevent natural gas leaks, and to keep you and your family safe. Always use high-quality materials for this job, turn off natural gas before starting, and ensure that your pipes are clean and dry before applying sealant.
Make sure that you are using only joint compound, and not plumber’s putty, as they are not of the same quality, and are not meant for the same tasks. Be sure to check all best-by dates on your products, and refrain from using any sealant tape older than three years, and any unopened joint compound older than eight months.