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Teflon Tape on Brass Fittings | Should You Use It?

In this article, we’ll discuss the best way to seal threaded brass fittings, which thread sealant is the top choice, and why using Teflon tape the wrong way can cause leaks. But first of all, should we even use it?

You should use Teflon tape on brass fittings because it prevents leaks. You could also use pipe thread sealant. The only time you don’t need to use Teflon tape on brass fittings is when it has a sealant or a rubber gasket. Make sure the Teflon tape goes in the same direction as the threads.

The Best Way To Seal Threaded Brass Fittings?

The best way to seal threaded brass fittings is as follows:

  1. Wipe the threaded fitting with a microfiber cloth to remove the debris. Old fittings will likely have pipe dope or worn Teflon tape. It’s important to remove these bits and pieces to ensure the tape makes complete contact with the fitting. Don’t forget to clean inside the female end, too.
  2. Firmly press a layer of Teflon tape on the threaded fitting and wrap it in the same direction as the threads. Most threaded fittings go clockwise. If you wrap the tape in the opposite direction, it’ll slowly peel off when you twist it into the female end of the pipe.
  3. Wrap the threaded fitting three to five times, depending on its thickness. The thinner the pipe and the deeper the threads, the more Teflon tape you’ll need to use. Most experts recommend three wraps, but do your best not to exceed five wraps. Too much Teflon ends up causing more harm than good.
  4. Press and hold the end of the Teflon tape to seal it to the brass fitting. Loose Teflon tape will fall apart and leak within a couple of days. Always pull the tape snugly when wrapping around any threaded fitting. Push the torn end to ensure it’s flush with the rest of the tape, stopping it from peeling off the fitting.
  5. Add pipe thread sealant if the manufacturer recommends it (or if you’re working with gas fittings). Some brass fittings require additional sealants. You’ll rarely need to add a second sealant for brass fittings that deal with water, but it’s worth checking the manufacturer’s suggestions beforehand.

Brass fittings need Teflon to prevent leaks, but you shouldn’t overdo it. Wrapping a fitting too many times can make it difficult to achieve a complete seal. The good news is that there are numerous Teflon tapes and thread sealants you can choose from to find the perfect fit for your brass fittings.

A Plumber Wrapping Teflon Plumbers Tape Onto Pipe Threads Correctly
The right way
Someone Wrapping Teflon Plumbers Tape Onto Pipe Threads the Incorrectly
The wrong way

Best Thread Sealant For Brass Fittings

This heavy-duty pipe sealant found on Amazon is what I recommend for brass fittings. It’s rated between -200 degrees to 500 degrees Fahrenheit. If you prefer Teflon tape, try this alternative thread sealant or pipe dope. It has everything you need to seal almost any brass fitting throughout your house.

Let’s take an in-depth look at both of these to see which one is right for you.

When it comes to quality pipe sealant, please use a high-end sealant that fills the cracks with hardening grains that bond to the surface. It works on metal, plastic, and many other materials. A thorough application can withstand up to 12,000 PSI, making it more than suitable for at-home and commercial repairs.

On the other hand, pipe dope typically comes with multiple rolls that you can use on brass, PVC, and other surfaces. I recommend that each roll is ½ an inch.

Do You Use Teflon Tape On Gas Fittings?

You should use Teflon tape on gas fittings unless the fittings have rubber gaskets. You can also use pipe dope to prevent the gas fittings from leaking. Pipe dope is messier than Teflon tape, but it solidifies much better than Teflon tape. Regardless of which sealant you use, it’s important to tighten gas fittings with a wrench, not by hand.

Consider these tips when using Teflon tape on gas fittings:

  • You can combine Teflon tape with pipe sealant. If you’re worried about your gas fittings leaking, don’t shy away from using gas pipe dope. It prevents leaks much better than most rubber gaskets. Furthermore, you can always remove or add more pipe sealant if necessary.
  • Always use Teflon tape rated for gas pipes (it’s typically yellow). Mitchell Plumbing Gas claims you should use yellow Teflon tape for most gas pipes. However, check the label to ensure it’s rated for gas. Yellow is almost always the Teflon tape color used for plumber’s tape that’s designed for gas fittings.
  • Check the plumber’s tape Fahrenheit rating. Gas pipes can get fairly hot, especially if they’re near water heaters and home heating systems. The Teflon tape should be suited for several hundred degrees. If it’s not the correct rating, the tape won’t prevent leaks. It’ll also likely melt and fall apart.
  • Use the dish soap spray bottle test to ensure there aren’t any leaks. Mix one drop of dish soap with two cups of water. Spray the solution over the gas fitting when the gas is on. If it bubbles, there’s a gas leak. If it doesn’t, you successfully sealed the gas fittings with Teflon tape (or pipe dope).
  • Make sure the tape covers all of the threads from top to bottom. There shouldn’t be any threads in the fitting without Teflon tape. If it’s not covered enough, you’ll undoubtedly have gas leaks. Gas fittings are much more susceptible to dangerous leaks compared to water fittings (in most cases).

Threading and sealing gas fittings can be nerve-wracking because we’ve all heard of the dangers of gas leaks. However, using the proper Teflon tape and pipe sealant with a wrench will prevent all leaks (assuming there aren’t any cracks in the pipe). Always turn off the gas line before opening and sealing it.

How Do You Stop Threaded Brass From Leaking?

To stop threaded brass from leaking, try this step-by-step method:

  1. Turn off the gas or water line. Never work on any plumbing while the primary substance is flowing through it. Not only can it cause leaks immediately, but it can also make it impossible to seal the threaded fitting. You can turn it off at the main line, though some fittings have manual valves.
  2. Loosen the pipe with channel locks. Never use hammers or anything else with blunt force. Although it could get the job done, you’ll risk breaking the pipe. Tighten one pair of channel locks on one pipe and use another pair to pry the fittings apart. Avoid bending the pipe to prevent long-term damage.
  3. Remove the old pipe sealant and plumber’s tape, then replace the pipe if there are any cracks. Again, remember to get rid of all of the debris from the male and female end of the fittings. You can use alcohol wipes to remove it, but always remove the solution with a microfiber cloth to create a clean layer for the sealant.
  4. Tightly wrap the threads with Teflon tape (replace any worn or broken gaskets if applicable). Hold the tape against the threaded fitting with one hand while tightly wrapping it with the other hand. Go around the fitting a few times, ensuring you cover the entire threaded portion that goes into the other pipe.
  5. Tighten the brass fitting to the female end that it was connected to. Use the same channel lock technique in reverse. Never tighten threaded brass fittings by hand; you won’t be able to prevent leaks. You could also risk serious injuries.

Quick Note: Properly sealed threaded brass fittings won’t leak for several years under regular pressure. If your brass fittings keep leaking, check if they’re rated for the water pressure or gas pressure they’re exposed to. Some fittings may need to be replaced because they loosen or corrode over time.

Related The Best Substitute for Plumbers Tape | With 3 Alternatives.

Can Too Much Teflon Cause Leaks?

A plumber putting on teflon tape

Too much Teflon can cause leaks because it makes it much harder to seal the fitting. When there’s too much plumber’s tape over the threads, you won’t be able to tighten it far enough to prevent water or gas from getting through. Make sure you only wrap the fitting a few times, then firmly press it onto the threads.

So, how do you know how much Teflon tape you should use? Ask yourself these questions:

  • How thick is the pipe you’re wrapping? If the pipe is thin, you should use between four to five layers of plumber’s tape. If the pipe is thick, we recommend sticking to three or four layers. One layer of plumber’s tape makes a significant difference in the threaded pipe’s thickness, so you wouldn’t want to overdo it.
  • Are you using Teflon tape on gas or water lines? On top of using the correct color for your threaded fitting, it’s important to only use about four layers of Teflon tape for most water pipes. If it’s a gas pipe, you shouldn’t exceed three (in most cases). Again the manufacturer’s recommendations supersede these suggestions if they say otherwise.
  • What kind of Teflon tape are you using? White Teflon tape is the most common type. However, if you’re using the wrong kind of Teflon for the job, you’ll likely have to use more layers. Keep in mind that nothing will suffice if the plumber’s tape isn’t within the recommended temperature range.
  • How thick is the plumber’s tape? Most Teflon tape ranges between 2.5mm to 3.5mm. If you’re using 2.5mm Teflon tape, you’ll likely need one extra layer to match the same effectiveness of 3.5mm Teflon tape. For example, three layers of 2.5mm Teflon tape equal 7.5mm, whereas three layers of 3.5mm tape equal 10.5mm.

While Teflon is often an essential part of preventing leaks, using too much of it can be detrimental. Make sure you can seal the threaded fitting completely. Almost none of the threads should be exposed out of the female end.

Which Is Better, Pipe Thread Sealant or Teflon Tape?

Pipe thread sealant is typically the better choice because it seals the threads much better. However, Teflon tape is cheaper and less messy. You can also apply it without any brushes or extra tools. Pipe thread sealant is better for gas pipes, whereas Teflon will do just fine for pipes with water flowing through them.

PVC Fittings Online claims most professional plumbers prefer pipe thread sealant because it creates a stronger bond. Whether you’re sealing PVC, brass, or galvanized pipes, you’ll have more luck with pipe dope. That being said, you can get along perfectly with using plumber’s tape with most at-home applications.

Consider these comparisons:

  • Pipe thread sealant (also known as pipe dope) is better if you’re working on commercial properties that can’t be repaired too often.
  • Teflon tape is the optimal choice for quick at-home solutions, such as toilet plumbing, showerhead sealing, or water heater repairs.
  • Pipe dope will work much better when working with gas fittings because it limits gas flow through the threads much more efficiently.
  • Teflon tape is a top option for those on a budget or people who have random minor repairs that need tending to.
  • Don’t shy away from using both sealants together if you want to achieve a reliable, long-lasting seal.

While pipe dope is almost always the better choice, there’s no reason to avoid Teflon tape. Countless repairs will last for several years if you use high-quality plumber’s tape. It doesn’t hurt to keep a roll of it on your workbench. You could also keep a bottle of pipe dope if you think you might deal with gas pipes.

Final Thoughts

Teflon tape is a staple because you can use it to seal most threaded pipes. Not only is it extremely affordable, but it’s also very effective and easy to use. Remember to wrap the Teflon tape clockwise (or whichever way the threads go).

For more, check out The Best Substitute for Plumbers Grease (And 5 Alternatives).