Tap into your inner plumber with this handy guide to the anatomy of a sink
The sink is the heart of a kitchen or bathroom. We use sinks to wash our veggies, brush our teeth, and fill our water bottles—but do you know how they work? Several parts of a sink, most of which rest below your countertop or vanity, allow you to control the flow of water. If you’re planning a renovation or making some DIY repairs, this guide will help you understand what you’re working with.
If you ever considered replacing your bathroom vanity, you’ve probably noticed all of the plumbing under your sink. Most of us are familiar with the parts of the sink we use every day, but it turns out what’s lurking below is actually essential to how the sink functions—from the way it receives water to the way the water washes into our sewer system. Here’s a full breakdown.
The faucet is the part of the sink where the water comes out. Depending on the type of faucet, it may contain a few different subparts. All faucets have a spout, the specific part where water exits the faucet. They also contain various gaskets, washers, screws (to create a watertight seal), and in most cases, an aerator. The aerator injects air into the water, helping reduce your water usage and bill.
The faucet controls are an integral part of every faucet. This is what helps you turn the water on and off, as well as control the temperature. Your controls will look different depending on the faucet design. You may have two knobs (with each one controlling hot or cold water), or you may have a single lever. Touchless faucets are controlled with sensors, though you may still have a knob or lever for temperature.
The sink basin is what most people think of when they think of a sink. This is the part that holds water that flows from the faucet. The sink basin will have a drain at the bottom that connects to your home’s plumbing. Most sinks also have an overflow hole with a pipe that attaches to the drain unless it’s a vessel sink.
The type of basin largely determines how to install the sink. For example, a vessel sink has a basin mounted above the countertop, while an undermount sink is installed below the countertop.
The drain is at the bottom of the sink basin, directing the flow of water out of the sink and into the rest of your plumbing and sewer system. You can stop water from flowing out of the drain by using drain stoppers, allowing water to collect in the basin so you can do work like soaking dirty dishes.
Before installing a new sink drain, ensure you understand which type of stopper you need. If you’re having issues with your drain, call a drain cleaning pro or plumber to inspect the parts of the sink drain and get them working properly.
The drain stopper is one of the most crucial parts of the drain and allows you to stop or start the flow of water out of the sink basin and into the drain. Bathroom and kitchen sinks have different types of drain stoppers. Gaskets and slip-joint nuts help seal the connection between the drain stopper and the plumbing.
Bathroom sinks have pop-up stoppers, where you press the stopper or pull on a rod to stop the drain. Pop-up stoppers include the following parts:
Pop-up plug: This drain plug stops the water so you can fill the basin.
Clevis strap: Also known as the clevis, the clevis strap connects the lift rod to the stopper. This mechanism may be broken if your drain won’t open or close.
Lift rod: This is the rod connected to the clevis strap that you lift to open and close your drain.
Clevis screw: This screw secures the lift rod to the clevis strap.
Pivot rod: This rod connects the clevis and the stopper, so when you pull the lift rod to move the clevis, the stopper also moves.
Spring clip: This clip holds the pivot rod in place on the clevis.
Instead of pop-up stoppers, most kitchen sinks have a stopper that helps catch food waste, and you can remove it to use the garbage disposal. The parts of a kitchen stopper include:
Strainer basket: This basket sits over the stopper and collects food waste. Some homeowners add an additional strainer basket over this basket if they have an issue with clogs.
Stopper: The stopper sits at the entrance to the drain and holds the strainer basket.
This sink drain component, a small section of piping, serves as a bridge between your drain and P-trap. It helps water flow from the sink and into your home’s plumbing system.
The P-trap is one of the most notable sink plumbing parts. This sink component consists of two pipes—a J-bend pipe and a wall tube—connected by slip-joint nuts. Each part serves a different purpose:
J-bend pipe: The curve of the J-bend pipe holds water, which acts as a barrier to prevent sewer gases from wafting up through your drain. If you have a smell in your bathroom drain, it could mean your J-bend pipe is dry. If your J-bend pipe dries out or springs a leak, sewer gases can come up through the pipe and enter your bathroom, causing unpleasant odors.
Wall tube: The wall tube connects the P-trap to the rest of your home’s sewer line.
A cleanout makes removing clogs and debris from your drainpipes easier. Instead of removing the entire drainpipe to access the clog, you can unscrew the cleanout and clear the clog from there.
Depending on your specific sink plumbing parts, your P-trap may have a built-in cleanout plug at the bottom of the J-bend pipe. If not, a separate cleanout pipe will be attached to your under-sink piping (on one side of the P-trap) before it enters the wall.
A sink has two water supply lines that bring hot and cold water to your faucet. These lines attach to your faucet controls, allowing you to control the flow and temperature of the water.
Shut-off valves connect to the water supply lines and stop the flow of water to your sink’s plumbing. You’ll find two valves—one for hot water and one for cold water—and you can operate them by turning the handles.
If your sink doesn’t have a shut-off valve, turn off your home’s main water supply to make sink repairs.
Kitchen sinks tend to be more complex than bathroom sinks and have some additional parts and upgrades.
Washing your dishes and cleaning your sink is a lot easier with a spray head. This optional and movable feature connects to your sink’s water supply lines via a spray hose in the faucet, or you can mount it on the sink. With a spray head, you have more control over the direction of the water.
These decorative metal pieces hide holes used for plumbing. You’ll commonly find them over the faucet hole and between the faucet and countertop on kitchen sinks. If your sink plumbing parts are visible and not tucked inside a cabinet, you can place an escutcheon where your pipe enters the wall.
A garbage disposal helps remove food waste by breaking down the food until it’s small enough to wash away into the sewer system. This upgrade goes under the kitchen sink between your drain and the P-trap.
The dishwasher drain hose removes water from the dishwasher. It has a loop at the top, which keeps dirty water away from your kitchen sink. You’ll find this drain hose in the cabinet under your sink, and depending on your setup, it connects to the airgap and the garbage disposal or the drainpipe.
The average sink installation costs $225 to $650, but once you install a sink, you can DIY most maintenance. Here is some of the maintenance you can do:
Clean your sink regularly: Use non-abrasive materials and gentle cleaners to clean your sink. Vinegar-based cleaners or baking soda and dish soap work wonders.
Mind your sink’s materials: Certain materials have their own quirks. Stainless steel can scratch and get hard water stains, while porcelain is susceptible to cracks. Learn the nuances of your faucet, basin, and piping material.
Prevent clogs: Avoid rinsing food waste down the kitchen sink and hair down the bathroom sink drain. Regularly remove and clean your drain stopper.
Don’t pour harsh chemicals down the drain: Avoid using corrosive chemicals like liquid drain cleaners or undiluted bleach down the drain because it can damage your pipes.
Use your garbage disposal correctly: Don’t put fibrous foods like banana peels or eggshells down the disposal, and always run cold water while using it.
Bring in a pro for repairs: If you notice that parts of your sink are beginning to fail, it’s best to bring in a sink repair pro. Small fixes can turn into big repairs if they’re put off for too long.
Most sink repairs cost between $150 and $500 if you hire a pro, but it depends on the issue. You can save about $45 to $200 per hour on labor costs by doing the job yourself. Some DIY repairs, like replacing a worn-out washer, will only cost a few dollars in parts.
That said, certain repairs are more difficult than others. You may be able to remove your sink drain and fix a clog on your own, but you’ll need extra hands to remount an undermount sink that falls out of place. When serious plumbing is involved, it’s best to hire a sink installer near you to get things back in order. A DIY gone wrong can lead to bigger repairs and issues, like water damage or cracked countertops, and could end up costing more than hiring a pro in the first place.
