5 Steps To Replace Pipes Under Kitchen Sink

The plumbing fixtures under your sinks are responsible for helping you eliminate different categories of kitchen wastes. However, you’ll need to replace them at one point in time due to the long-term wear and tear effect.

So how do you replace pipes under the kitchen sink?

The simplest way is to get new pipes and nuts, then remove all old fixtures after proper identification. Attach a new drainpipe by taking its thread and fixing it using a slip nut. Ensure that you do not tighten the new fixtures excessively. Lastly, test your installation by flooding the sink.

Also, you will need the following materials: Drain traps, Tape, Sink connectors, Pipe and adjustable wrench, PVC pipe, Bucket, Cleaner, Glue

To make it easier, take this list of items with you to your local tool store. Also, let the storekeeper know the type of drain pipe you wish to replace to get a good recommendation.

As soon as you get the materials, turn off the water supply system or let everyone in the house know that you’re about to work on the pipes to prevent flooding due to unexpected water flow.

5 Steps To Replace Pipes Under Kitchen Sink

  • Step one:
    Get a container and put it under the drain. Ensure that the water source is switched off. After this, bring out the drain pipes one after the other. You can seamlessly do this by identifying the drain trap and cutting the pipes below it. Once you’re done with this, unscrew the drains to bring out all the pipes.
  • Step two:
    Get the new drain pipe and surround its thread with tape. Once this is done, attach the tailpipe to the sink with a nut. The next thing is to fix the tailpipe to the drain by threading it till it’s tight. However, do not overtighten it. If you have a dual sink, you’ll need a T-section to join the double tailpipes.
  • Step three:
    At this stage, you must ensure that the sink trap is attached to the tailpipe. Make a line on the tailpipe before removing it if you don’t have adequate space to connect everything. To make the pipe fit, you can use a saw to cut and adjust it. Ensure that you assess the tailpipe before attaching it to the P-trap.
  • Step four
    Put the washers into the nuts while ensuring that the threads are facing outwards. The next thing is to tighten the T-traps and ensure that you don’t do that excessively. This is because of future adjustments where you have to remove the pipe due to blockage or cleaning. Also, the threads could crack and lead to a leak if you tighten them excessively.
  • Step Five
    Do a quick test of your installation. Turn on the water source, allow the sinks to get filled with water, and inspect any leak or crack. If you find one, look for its source and adjust accordingly. If at any point, you get confused about the next step, you can watch a live demonstration here.

We recommend that you take note of the following precautions while attempting this replacement.

  • Ensure that your materials are complete before starting the procedure.

  • Ensure that the materials and tools are not expired, faulty, or broken. The effect of replacing a defective fixture with a similar type is disastrous.

  • You can put on work gloves or aprons to protect yourself from cuts and possible stains.

  • Try as much as you can to repair at a stretch and not abandon the project halfway.

  • Ensure that the new parts are compatible with the former ones.

How do you remove plumbing under the kitchen sink?

Switch off the valves and ensure that the faucet can’t supply water before you proceed. Place a container under the trap. The next thing is to find the nut that connects the trap to the tailpiece and remove it by turning or unscrewing it with a wrench. Lastly, remove the swivel nut and detach the trap.

You’ll need a wrench if the nut is metallic. Otherwise, you can dislodge it with your hands. After removing the trap, you can empty the water inside and clean it.

If your traps are metallic, you should replace them with plastic versions, especially if the nut rusts overtime. You should follow these same steps if you wish to remove S-traps that are attached to the wall.

What are the pipes under the kitchen sink called?

The pipes beneath your kitchen sink are known as P-traps. They are called traps because they are curved and trap all the dirt emanating from your sink. These curved pipes are installed alongside other fixtures in your sink to make a complete drainage system.

Some of these parts include the sink, which is the main and the biggest component. It comes in various sizes and is responsible for taking in all your washing residues.

The sink drains through many fixtures. There’s usually a strainer that goes down the hole in the sink. This strainer connects the sink’s tail to the remaining fixtures. Some plumbers attach a dust bin to the strainer.

There’s also a gasket, retainer, and washer under the sink. The retainer serves as a nut that connects the sink to the body. Also, the sink has a tailpiece that connects to the strainer through threads. The tailpiece is a significant component of the drain trap and is connected by slip nuts. You also have an escutcheon at the back of the wall that conceals the connectors. The sink’s content leads through the trap to a drain pipe.

Another significant component of the sink system is a P-trap. It is called this way as it traps harmful glasses when they enter your home. It is situated under the sink and shaped like an inverted P.

The dynamics of water flow in the sink is such that all fluids go down the sink through the trap and out the drain pipe. However, the exit point of the drainpipe is higher, and some water settles at an end within this pipe. This is not an anomaly, but the water serves to trap harmful sewer gasses from going up the drain. You don’t have to worry about replacing the water, as this is automatically done whenever you use the sink.

There’s also a big washer under every connection that provides a tight seal. This way, the traps can be successfully attached to the tailpiece through threads. If you need to inspect a block, check the traps. Some models come with a plug underneath so that you won’t need to remove the whole system for inspection.

How much does it cost to replace a pipe under the sink?

The average cost of replacing a pipe under the kitchen sink is $100 for most repairs. However, the actual price depends on the job’s size, your conditions, and the coating option you want. Some plumbers might give you a sizable discount based on your status.

Repairing kitchen pipes and fixtures costs far less than replacing pipes in other parts of your home. This is because most of the materials needed are very accessible. You can also ask your plumber if they charge an hourly rate. The average rate ranges from $45 to $200. This is a more economical option as fixing might not be more than an hour.

If you’re repairing yourself, you probably will save a lot of money and resources. All you need in this case is the money to buy the replacements. However, it would be best if you studied the repair steps carefully, so you don’t make a faulty replacement that will necessitate you having to call a plumber afterward. This will cause you to incur double expenses.


The kitchen sink does most of the dirty work in your cooking space. As such, you must ensure they are in perfect working conditions at all times. Usually, there’s an occasional need for swift replacement as the pipes undergo corrosion due to the long-term deposit of waste residues. The replacement might also be due to clogs and persistent blocks.

However, delaying the repair at this stage might spell more trouble than you expect. If the damage turns out to be a leak, it might stain your floors and put permanent damage to your walls. As such, we’ve laid out the steps for you to overcome this seamlessly.

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