Are you dealing with a leaky or corroded metal P-trap under your sink?
You may be wondering if it’s possible to replace it with PVC parts instead.
The good news is that it is possible, and it can be a DIY project for those who are handy with tools.
In this article, we’ll go over the steps involved in replacing a metal P-trap with PVC, including what materials you’ll need and any potential challenges you may face.
So, let’s dive in and learn how to upgrade your plumbing system with PVC!
Can You Replace Metal P-trap With Pvc
Yes, you can replace a metal P-trap with PVC parts. PVC is a popular material for plumbing because it’s lightweight, easy to work with, and resistant to corrosion.
To replace a metal P-trap with PVC, you’ll need to purchase a PVC P-trap, pipe, and fittings that match the same diameter as the metal pipes you’re replacing. PVC drain pipe comes in two different diameters: 1 1/4 inches and 1 1/2 inches. Make sure to buy material that’s the same diameter as the metal pipes you just removed.
Next, cut the PVC pipe to the lengths that you need with a hacksaw. A rubber coupler connects the PVC pipe to the steel drainpipe. The drainpipe coming out of the wall has an adapter on the end. This adapter has a washer and slip nut and works just like the other joints in your drain assembly.
If your drainpipe is plastic, you shouldn’t have any problems. But if your drainpipe is old galvanized steel, you might run into corrosion that makes the slip nut almost impossible to loosen or retighten. In this case, you’ll need to bypass those rusty old threads by unscrewing the old slip nut and cutting it off with a hacksaw if necessary.
Then, buy a plastic trap adapter, a rubber transition coupler, a section of plastic pipe, and cement. The pipe and adapter can be PVC (white) or ABS (black); just be sure to get the right cement for the type of plastic (PVC also requires purple primer). Cement the adapter to a 4-in. piece of pipe and join the plastic pipe to the old metal pipe using the rubber coupler.
It’s important to note that slip joint fittings can be used with both metal and PVC pipes, so there’s no need to worry about mixing materials as long as they are the same physical size. However, if the pipe into the wall is not connected with a slip joint, you may need to cut the pipe out of the fitting in the wall or hire a plumber who knows how to do it without damaging the pipe in the wall.
Why Replace A Metal P-Trap With PVC
There are several reasons why you should consider replacing a metal P-trap with PVC. The first reason is that metal pipes are prone to corrosion, which can cause leaks and eventually lead to water damage. PVC pipes, on the other hand, are resistant to corrosion and will last longer without the risk of developing holes or cracks.
Another reason to switch to PVC is that it’s a lightweight material that’s easy to work with. This means that installation is faster and simpler than with metal pipes, which can be heavy and difficult to maneuver. Additionally, PVC pipes are less likely to clog than metal pipes, which can save you time and money on maintenance.
Finally, PVC is a more affordable option than metal pipes. While the initial cost may be slightly higher for PVC materials, they will last longer and require less maintenance over time. This means that you’ll save money in the long run by avoiding costly repairs and replacements.
Materials Needed For The Project
To replace a metal P-trap with PVC, you will need the following materials:
1. PVC P-trap
2. PVC pipe (same diameter as the metal pipes being replaced)
3. PVC fittings (same diameter as the metal pipes being replaced)
4. Rubber coupler
5. Plastic trap adapter
6. Cement (appropriate for the type of plastic being used)
You may also need a hacksaw to cut the PVC pipe to the necessary lengths and a rubber transition coupler to join the plastic pipe to the old metal pipe. If the old slip nut is corroded and difficult to loosen or retighten, you may need to cut it off with a hacksaw as well. Additionally, if the pipe into the wall is not connected with a slip joint, you may need to hire a plumber who knows how to remove it without damaging the pipe in the wall.
Removing The Old Metal P-Trap
Before you can replace the metal P-trap with PVC, you need to remove the old metal P-trap. First, locate the nuts that hold the P-trap to the tailpiece and the drain line. You should be able to unscrew these nuts by hand, but if they’re stuck, use spray lubricant to loosen them.
If you’re unhooking a double sink, you’ll need to loosen the nuts on both tailpieces. Once you’ve removed the nuts, you can take off the metal pipes by pulling them away from the tailpiece and drain extension. Be careful not to damage any other parts of the plumbing system when removing the P-trap.
If you have old metal pipes, they may have worn thin and could collapse when you put pliers on them. In this case, be gentle when removing the P-trap and use a hacksaw if necessary. Once you’ve removed the old metal P-trap, you can proceed with installing the new PVC P-trap.
It’s important to note that if you’re not comfortable working with plumbing or if you encounter any issues during this process, it’s best to hire a professional plumber to handle the job for you.
Measuring And Cutting The PVC Piping
To measure and cut the PVC piping, start by using a hacksaw to cut the pipe to the lengths that you need. Whether it’s metal or plastic, the cuts do not have to be perfect due to the overlap. Dry fit the pieces to make sure they are fitting correctly.
PVC drain pipe comes in two different diameters: 1 1/4 inches and 1 1/2 inches. Make sure to buy material that’s the same diameter as the metal pipes you just removed. If you’re unsure of the diameter, you can use a digital caliper to measure it easier.
When cutting the piece of drain pipe that goes into the wall, make sure to cut it long. It will go inside the pipe a couple of inches and be held in place by the nut and washer. If you cut it too short, it won’t fit properly and may cause leaks.
It’s important to note that when using a rubber coupler to connect the PVC pipe to the steel drainpipe, you should leave at least 1.1 inches sticking out. This will ensure a secure and tight fit. The screws on the coupler should be tightened about 5 ft-lb, which is about as much as you can do with a 5/16 nut driver.
Installing The New PVC P-Trap
Once you have removed the old metal P-trap and cut the PVC pipe to the appropriate lengths, it’s time to install the new PVC P-trap.
First, attach the wall bend (long elbow joint) to your trap adapter. If you need a trap adapter, make sure to install it before proceeding. The trap adapter will allow you to use the convenience of screw-on fittings in your setup.
Next, attach the PVC P-trap to the wall bend using a slip joint coupling. Slip the coupling over the end of the wall bend and tighten the slip nut until it’s snug. Then, slip the other end of the coupling over the inlet of the PVC P-trap and tighten that slip nut as well.
After that, connect the PVC pipe to the other end of the P-trap using another slip joint coupling. Slip the coupling over the end of the P-trap and tighten the slip nut until it’s snug. Then, slip the other end of the coupling over the PVC pipe and tighten that slip nut as well.
Finally, test your new PVC P-trap by running water through it and checking for any leaks. If you notice any leaks, tighten the slip nuts a bit more until they are snug.
Overall, replacing a metal P-trap with PVC is a simple process that can be done with a few basic tools and some PVC parts. By following these steps, you can ensure that your plumbing system is functioning properly and efficiently.