Parts Of A Bathtub

You might be surprised by how many parts are involved in your bathtub. From the plumbing to the drainage to the tub itself, all the pieces need to work together in harmony.

It helps for homeowners to have a general understanding of their bathtub, especially if you plan to do any DIY maintenance.

The Tub


The tub itself is the main component, and it’s probably what you think of first. It can be a rectangular or oval shape.

Some larger luxury tubs are even circular.

The tub stores the water while you bathe. It is outfitted with faucets to let water in, along with a drainage system to let the water out.

You can block the main drain to fill the container with water or, if you’re showering, let the water drain consistently throughout use.

Some new tub models include thermostat valves that allow you to control the water’s temperature more precisely. This helps keep you from being potentially burned.

For the most part, though, you don’t need to worry about burns as long as you carefully use the faucets.

Water Supply

water supply

The water supply will typically come from your central plumbing instead of the bathtub itself. When you turn on the faucets, hot and cold water will flow through the pipes.

Water supplies might come from city systems or an underground well, depending on your location. It’s important to regularly test the water for pollution and damage.

Warm water tends to come from a water heater in your house or apartment. Cold water flows through a condenser or tower.

It’s helpful to know where your water comes from as a homeowner, but you likely won’t need to interfere with it.



The showerhead or spout is an important component of the bathtub, and it’s attached to the piping that controls your water supply. Showerheads come in a variety of shapes and sizes.

Some are detachable, while others are bolted into the wall.

The flow of water will vary depending on the size of the showerhead. Efficient models will often have lower flow so that they can conserve water.

There are even components built into most showerheads to automatically restrict the flow.

Showers mix cold and hot water by using control valves. This allows you to get the right mixture for a comfortable temperature.

When you’re working with an older unit that lacks precise controls, you should be cautious so you don’t accidentally burn yourself.

Planar Cross

The planar cross is a type of linked piping that is used to control the flow of water. You usually won’t find it outside of bathtubs.

The term “planar cross” comes from geometry, where it is used to describe the cross of two different planes through a solid object.

Shutoff Valves

shutoff valves

Shutoff valves are used to control the flow of water in your piping. There are two main types of valves: primary and fixture.

A fixture valve, as the name implies, is one that’s attached to a fixture in the house. Each one is meant to be installed with a specific “stop” valve.

You can use these to cut off the water flow to a malfunctioning item without needing to turn off your entire water supply.

With that said, fixture valves have only become the norm within the last few decades. If you’re working with older items, there might not be a specific shutoff valve built into this plumbing.

When this is the case, you do need to shut off your entire central water system each time you intend to fix a problem. For this reason, it’s a good idea to update old plumbing fixtures with newer options.

Diverter Pipe

diverted pipe

The diverter pipe helps to divert the flow of water away from an area, or to move the flow of water to a central point. Its purpose is to control where exactly the water flows.

When it comes to your tub, a diverter pipe is likely responsible for how warm and cold water emerges from the same faucet. After flowing to the tub in separate pipes, the diverter design guides both flows of water into one central pipe.

That way, you get a mix at the perfect temperature.

In addition to bathtubs, you’ll find diverter pipes in appliances like sinks and outdoor faucets. Sudden low water pressure is often caused by a worn-out diverter pipe that needs to be replaced.



Your bathtub drain can sometimes be a pain to maintain, especially when it gets backed up with clogs. But the drainage system is what allows you to easily remove the water from the tub when you’re finished bathing.

There are several things that can lead to a blocked tub drain, including hair and soap scum. Your drain is more likely to become blocked if you don’t have any kind of “trap” that can keep hair and grime from accumulating in the pipes.



The rim refers to the top of the bathtub. It creates a stable base so that the tub remains in place.

Many people use the surface of the rim to hold their soap, shampoo, and other accessories.

Another important aspect of the rim is that it traps water when the tub is about to overflow. Though it can’t stop a true overflow issue, it can prevent water from dripping down the sides when the tub is filled to the brim.

That’s essential for preserving your bathroom floor.

Flexible Connector

Flexible connectors are a type of plumbing tool that are often used in bathtub setups. There are different kinds depending on your needs.

The basic job of one of these connectors is to link a pair of pipes that aren’t otherwise able to be connected.

Flexible connectors tend to be crafted from braided steel. Because of their flexible design, they can be stretched through areas that a straight pipe can’t reach.

They can also be used with the plumbing system of nearly any house.

If your bathtub plumbing needs extra connections, one of these tools is your most likely option.

Overflow Pipe

overflow pipe

Every tub is outfitted with an overflow pipe. This pipe is positioned between the drain and the connectors.

When the water gets too high in the tub, the overflow drain begins to siphon it out. This diverts the water away from the drain and lessens the overall load.

Overflow pipes work automatically when the water level reaches a certain point. They’re important for preventing potential accidents.

Waste Outlet

waste outlet

The waste outlet doesn’t siphon anything into or out of your tub. Instead, its job is to keep waste out.

The outlet pulls waste into the drain and prevents it from flowing back up the pipes. That way, there’s no overlap between used toilet water, used bath water, and your regular water supply!

Without a waste outlet, it would be much more difficult to keep your plumbing and water supply clean.

P Trap

A P trap is a type of plumbing that’s often installed in sinks, but can be part of bathtubs too. This fixture is stretched over the drainage system.

It prevents debris like hair and soap from sliding down the drain and becoming caught deep inside the system.

The other purpose of a P trap is to keep gases from the sewer from flowing up the pipes and into your house. These fixtures might be crafted from steel or PVC piping.

While both materials work well, steel is favored for exposed areas because of its aesthetic appeal.

The exact setup of a P trap will vary depending on the building codes in your state or country.

Decorative Panel

decorative panel

Decorative paneling is used to conceal the internal plumbing in your bathroom. It is typically made with tiles or stones.

You’ll use this paneling to conceal the pipes built into the floors and walls.

Some bathtubs might come with their own decorative paneling for the walls around the tub. It depends on how disruptive the design is to the general wall fixtures.


The bathtub lining is the part of the wall that the bathtub is secured to. Most bathtubs will have the wall lining on at least two sides, some with three.

Bathtubs are meant to drain into the piping system. But if there’s a malfunction that causes drainage into the lining instead, that can lead to water damage and serious complications.



Faucets are the controls that you use to fill the bathtub. You can turn them to control the temperature and the force of the water.

Faucets themselves are built with several different components. These allow them to regulate and sometimes purify the water with the most efficient setup.


Your bathtub is made up of many different parts, all of which help it to fill and drain efficiently. Once you understand how the plumbing and construction works, you’ll have a much easier time dealing with basic home maintenance as well.