Bathtub Drains: Right, Left, Center, and Reversible

When it is time to pick out a bathtub, the main concern of most shoppers is the look and feel of the tub itself. But there's another important consideration that you can't overlook—the location of the bathtub drain.

Kingston Brass allows you to be flexible when choosing your tub layout and drain finish. With multiple colors, finishes, sizes, and designs available, it’s easy to put the information in this article to good use in the style of your choice.

Bathtub Drain Location: An Overview

There are several options when deciding where to place the drain on your bathtub. You could choose a right- and left-hand drain, which means that the drain hole at the bottom of the tub is either on the left or the right (when viewed from the entry point).

There are also center and reversible drains to choose from. A center drain is just like it sounds—the drain is located in the center of the tub. A reversible drain, however, is a bit of a misnomer. The drain can be found on either the right or left side, though this is achieved by reversing the direction of the tub, not swapping the physical drain location itself.

Why Is Bathtub Drain Location So Important?

While this may seem like an unimportant decision, it can actually save you hundreds or even thousands of dollars.

That's because the location of your drain affects the layout of the plumbing in your bathroom. Suppose you choose a left-hand drain when your drain pipe is on the right side, for example. In that case, your plumber will need to do extensive work to move the drain pipe to the other side of the tub—a choice that may even require raising your tub off the floor, so there's enough of a downhill slope for water to drain effectively.

Bathtubs are available in many different styles, colors, shapes, and sizes. Many materials are available, including acrylic, fiberglass, and cast iron. The moral of this story is that you can choose the tub you want, but don't forget to plan ahead for your drain location!

Below, we'll explore how a tub drain functions, the different styles of tubs available, and how to choose the location of your bathtub drain.

A Quick Course on Bathtub Drains and Plumbing

Understanding the basics of bathtub drains doesn't require a physics degree. Water flows downhill, so the drain is located at the lowest point. Usually, there's also an overflow drain in case you get distracted while filling up the tub.

The inner workings of the bathtub drain are a bit more complicated. That overflow drain typically has a toggle switch, allowing water to drain out of the bathtub when opened. When this toggle is closed, it activates a stopper or plunger to block the drain pipe. This is what lets you fill your tub.

When water flows into your drain, it first moves down a tailpiece and into a P-trap. A P-trap is a U-shaped piece of pipe that always has standing water in it, even when the tub is dry and empty. All bathtubs and all other plumbing fixtures are required to have a P-trap. The standing water in the trap prevents smelly sewer gases from traveling up the pipe and into your bathroom. You can think of it as a seal against the sewer.

Once the water moves through the trap, it flows down a sloped drain pipe. This connects to the house's main drain pipe, which moves water out of the building and toward either a septic tank or a municipal sewer.

Another important element to understand is the vent stack. This is a vertical pipe that runs from your main drain line up through the roof of your house. It doesn't carry water, but its purpose is to prevent a vacuum from forming. In most places, it's required to have a vent pipe within five to eight feet of your tub.

Without a vent stack, draining water out of your tub, toilets, and sinks would be like trying to drain water out of a straw with your thumb covering the top. Remove your thumb, and the water exits.

It's important, therefore, to know where your existing drain pipe and your vent pipe ar