How to Plumb a Kitchen Sink

Have you ever wondered how to plumb a kitchen sink? Odds are, if you’re involved in installing a new kitchen sink, the answer is yes.

Plumbing a kitchen sink involves removing the old one, installing new drain lines , drainpipes, and supply lines.

Reasons to Plumb a Kitchen Sink

Given how tedious and cumbersome a job it can be to upgrade your sink, you might be putting it off. If possible water damage is becoming an issue, you may want to deal with the problem and save yourself some money in the long run.

Outdated Plumbing

The fact of the matter is, your drain pipes might not be able to handle the sheer volume of water that goes down the sink drain. Standards change in building codes and regulations, so should your drain assembly and faucet.

No likes dealing with an old sink that has inferior PVC pipes, hopefully, no lead pipes are in your home.

Plumbing Tools and Supplies

Before you get started plumbing your kitchen sink, remember to gather all of your tools and supplies.

  • Pipe wrench
  • Plumber’s putty
  • Silicone caulk
  • Rubber gaskets
  • Teflon tape
  • Utility knife and putty knife
  • P-trap assembly
  • PVC pipe
  • Tape measure
  • Tubing cutter
  • Drain trap kit

Types of Sinks

There are a multitude of available sinks and sink basins to choose from when it comes to replacing your old sink. For the sake of brevity, I’ll cover the 3 main types.

Drop-in Sink

Some people call them top-mount sinks, they’re one of the most popular choices because the installation process entails placing them inside of a prefabricated hole in the counter.

Farmhouse Sink

Often called an apron sink, they consist of a larger sink tub and can require installing new base cabinets that are compatible with it.

white porcelain sink

Under-mount Sink

Given their design, they’re often used with granite countertops and solid surfaces. They require under-the-counter installation and have an edge that rests below the countertop.

They are great for people who like an easy cleanup kitchen and can afford it.

Sink Parts

Knowing the terminology and what it means will help you tremendously on your journey of kitchen plumbing enlightenment.

Drain

Located within the sink, the drain opening is the connection between the sink basin and the drain pipe. The drain pipes feed into the waste pipe of your home or apartment and by extension connect to the sewer or septic tank.

It’s important to keep the drainage system in proper working order, so you may need to service it at least once a year.

P-Trap

The p-trap is designed to prevent sewer gases and the likes from escaping up the pipes. This is accomplished by a small pocket of water that gets trapped within the u-shaped pipe, which prevents gases from traveling upwards.

More expensive versions feature a trap adapter, which can come in handy.

Sink

The sink is composed of several different parts.

Faucet

The faucet is the connection between your main water supply to the kitchen and the rest of your home.

Sink Bowl

Sometimes called a sink basin, as the name suggests it’s the part of the sink that houses the drain hole and is where water is deposited from the faucet.

Sink Drain

This is the drain opening in the sink where the strainer is seated, the p-trap is located just beneath.

Sink Tailpiece

This is the part of the drain that functions as the connection between the sink drain, where the strainer goes, and the drain pipe. Usually, this is connected to a wall tee that helps hold it in place.

Shutoff Valves

As the name implies, the shutoff valves are designed to cut-off the water supply to the pipe in the event of an emergency or for routine maintenance.

Not knowing where these are located can cause quite a problem if something ever happens.

Waste Line

Otherwise referred to as the drainpipe, its function is to expel all water and debris that enters the drain. You don’t want this failing on you, otherwise, it’s water everywhere and not a drop to drink.

plumber with plumping tools

Getting Started

The first thing you need to do before you install a sink is to determine your budget and gather all necessary information for the project.

Avoid costly mistakes and plan out your plumbing before you get started, you’ll be thankful for it later.

Take Measurements

Knowing the length of the pipes, sink, and faucet you need is a crucial process in installing a sink. For instance, if the new sink is deeper or wider, you’re going to have some problems.

Measure twice, cut once.

Countertops

As much as you might love them, you will have to remove the current sink from the countertops and risk damaging them in the process. Hopefully, the countertop hole is big enough, but custom sinks can be a hassle.

If it isn’t, measure the countertop opening and cut out any excess. Precision is key.

Pipes

Take the time to understand the pipes of your kitchen, chances are you might need to replace some of them when installing a new sink. Although they may be cheap, don’t buy more than you need.

Copper Pipe

In most modern homes, copper pipes are used as the supply tubes for your waterline. Most of the copper pipe for the sink will be located within the wall.

Although it’s tempting to some, it’s not recommended to pull the copper pipes out of the walls for a quick buck.

PVC Pipe

PVC pipe is the most common type of pipe in homes. Typically, PVC pipe is used for the waste line in most homes, which is the majority of the plumbing. When comparing PVC vs CPVC, you’ll find they each have specific uses.

It takes a lot of planning to plumb a sink, do the job right the first time. You may need to consult the family handyman, so to speak, assuming it’s not you.

Kitchen Sink Installation Process

The process to install a new sink can be a messy job and it often requires more than one person. When considering a new sink for your kitchen you need to determine if the pipes need to be upgraded, as well as new drain lines, the water supply valve, and your water supply lines.

There’s a reason why remodels cost so much, avoid any mistakes and get the job done right the first time.

The steps listed below assume that you’ve already removed the old plumbing and sink or that it hasn’t been installed yet and that measurements have been taken.

plumber under the sink

Steps

  1. Measure the countertop hole to ensure it’s large enough, cut to size if needed.
  2. Determine if you need to lower or raise your drain pipe assembly.
  3. If applicable, install your garbage disposal, sometimes called a disposer, onto the side of the sink you want it on.
  4. Connect it to the wall tee with a slip nut.
  5. Install the faucet by feeding the sink tailpiece through the gasket and seal it with plumber’s putty.
  6. Secure the drain trap and the sanitary tee, ensure that the waste arm and tee are at an angle, you’ll most likely have to hunker to reach it.
  7. Place the strainer into the plumber’s putty and thread on the lock nut or slip nut that secures it in place.
  8. Remove excess putty from around the strainer with a towel or putty knife.
  9. Next, connect the shutoff valves to the faucet.
  10. Attach the tailpiece and the sprayer hose.
  11. Mantle the p-trap and its trap adapter to the tailpiece, seal the PVC pipes with PVC cement.
  12. Attach the dishwasher drain line to the waste line.
  13. Attach any additional items, such as a soap dispenser

Call a Plumber

If the job seems like too much, consider hiring a plumber to help you upgrade your home with new supply lines, a drain assembly, and drain line. For the cost, you might as well make sure the job is done right and keep uncertainty off the menu.

Tips

Before undertaking any home repair project, consider these tips.

  • Get set up before you start a project, gather tools and any plans.
  • Double-check your work to make sure there are no leaks or other plumbing complications.
  • Watch a few videos to see how the job is done.

plumber tools and equipment

If you’ve been wondering how to plumb a kitchen sink, then this information should have proven useful and you’re all set to install a new sink in your home. Now that you know how to install a kitchen sink, carry on.

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