If you're performing plumbing repairs or modifications, there's a chance you'll encounter a situation where you need to connect PVC to brass. In most cases, it's connecting a PVC fitting to a brass pipe, but it can also be the opposite. Either way, while connecting PVC to brass is possible, it's important to do it correctly to avoid leaks.
The best way to connect PVC to brass is to use a threaded PVC female adapter and screw it onto the threaded end of a brass pipe. However, you can also use a flexible PVC or Fernco coupling with stainless steel clamps when connecting two pipes. The one way that you should never connect PVC to brass is with a traditional PVC coupling or fitting, fastened with PVC glue and primer.
When connecting PVC to brass, using the right materials and following the proper procedures is vital. Otherwise, your connection will likely loosen, resulting in leaks, water damage, and mold issues.
Why is It Difficult to Connect PVC to Brass?
When it comes to plumbing, it's always easier to connect two similar materials than those that are polar opposites. For instance, connecting PVC to PVC, brass to brass, PEX to PEX, and so on, takes less time and effort. Although it's possible to connect different types of materials, it's more difficult because plumbing materials aren't always designed to be compatible.
In the case of PVC and brass, PVC is made of polyvinyl chloride and is mostly used for drains, vents, and sewer lines. PVC isn't aesthetically pleasing, so it's designed for functionality and performance rather than for decorative reasons. Brass, conversely, is made of hard, durable steel and is designed for both performance and aesthetics. Brass is often used in situations where it will be on display or visible to the general public.
In short, PVC and brass are about as different as night and day, which makes them an unorthodox combination. However, depending on your situation, connecting PVC to brass might be the only viable option.
Applications Where You Can Connect PVC to Brass
Here are some scenarios where you can safely connect PVC to brass.
- Connecting an outdoor sprinkler system or hose to a PVC fitting.
- Connecting an old brass drain to vent to a new PVC one.
- Transitioning from PVC to brass for a bathroom fixture or faucet.
- Remodeling an old house with brass pipes or drains and replacing damaged sections with PVC.
- Restaurant settings where hidden pipes consist of PVC, but visible pipes are brass.
- In addition to these situations, there are plenty of others where it's necessary to transition from PVC to brass or vice versa.
How to Connect PVC to Brass With a Female Adapter
The first option for connecting PVC to brass is using a female adapter, and here's how it works.
Gather Your Tools and Materials
- PVC or brass female adapter
- Teflon tape
- PVC glue
- PVC primer
- Wrenches or Channellock
Make the Connection
Once you gather your tools and supplies, here's how to make your connection.
1. Wrap Teflon tape around the threads on the male end of the brass pipe.
2. Make sure to wrap the pipe in the same direction as the threads. Otherwise, the Teflon tape will unravel when you screw the pipe into place.
3. Apply PVC primer to the inside of the female PVC fitting and the outside of the Teflon-covered male end of the brass pipe.
4. Apply PVC glue on top of the primer on both the pipe and fitting.
5. Screw the female PVC fitting onto the threaded end of the brass pipe.
6. After it's hand-tight, use a wrench or Channellock to continue tightening the fitting.
7. You will also need a wrench or Channellock on the brass pipe to hold it tightly in place.
This method works best if you connect PVC or brass with a threaded end to the opposite material. If you want to have the option of loosening the connection at a later time, don't apply any glue or primer. If you do that, however, you should wrap a few more rounds of Teflon tape around the brass pipe.
How to Connect PVC to Brass with a Fernco Coupler
If you connect a PVC pipe directly to a brass pipe without threads, the above method won't work. Instead, you'll need to make the connection with a Fernco coupling. Here's how it works.
Gather Your Tools and Materials
- An appropriately sized rubber or Fernco coupling
- Screwdriver
- Plumbers' grease or cleaner
- Reciprocating saw or handsaw
Make the Connection
Using a rubber or Fernco coupling, you can connect PVC and brass pipes of the same or different size. If, for example, you're connecting a 2" brass pipe to a 1" PVC pipe, you'll need a 2" x 1" reducer coupling. Once you have the right coupling, here's how to make your connection.
1. Make so that the ends of both pipes are smooth and even. Cut the ends, if necessary, with a reciprocating saw or handsaw.
2. Clean the ends with a rag and apply a small amount of plumber's grease to either end.
3. Insert the end of the brass pipe inside one end of the rubber coupling until it's halfway through the coupler.
4. Insert the end of the PVC pipe inside the opposite end of the coupler until it is halfway through.
5. The pipes should be touching or almost touching inside the coupler.
6. Use a screwdriver to tighten the clamp around either side of the coupler.
Perform a Test Run
Pull either end of the pipes in opposite directions to test your connection. They should stay firmly in place inside the rubber coupling. If they move at all, push them back into place and re-tighten the clamp around the coupling. Once you're satisfied with the tightness, turn the water on to the connection and check for leaks. If the connection remains dry, you're good to go!
Final Thoughts About Connecting PVC to Brass
Although some forethought and preparation go into connecting PVC to brass, it's a fairly common and easy job. Fortunately, brass and PVC use the same measuring system for their pipes, which makes them more compatible than other plumbing materials. However, because they're designed and composed differently, it's important to follow the steps above if you want to make a watertight PVC-to-brass connection.