Sanitary Tee Vs. Wye Pipes: Uses & Differences

Drain vent system components include sanitary tee and wye. They might be necessary for some plumbing work, but you may be confused by how similar they seem.

Especially which fits your drain system the most. Want to know the uses and differences between these two fittings? Well, we’ve researched this thoroughly to help you with this matter.

 A sanitary tee is used to direct liquid flow from a horizontal pipe to a vertical one—a wye transfers from vertical to horizontal.

The primary distinction is that sanitary tees have the shape of "T" and "Y" for the wye. Also, the first one changes the direction of the pipe by 90° and 45° for the latter.

This article will share more details about the uses and differences between sanitary tees and wyes. We'll also explain how to install them and whether you may use them interchangeably. So keep on reading to learn more!

This is a sanitary tee used in plumbing drain system, a PVC fitting - a draining wye pipe, angle 45 - Sanitary Tee Vs Wye Pipes Uses &amp Differences

What Are Sanitary Tee And Wye Pipes Used For?

Amateurs shouldn't attempt to build their own plumbing system.

However, some people continue trying, and some have moderate success. Knowing which fittings to employ to distribute their water flow properly is a critical component of their success.

You'll need to become familiar with the necessary tools when you first start doing any form of home improvement. When assembling a drainage system, you'll need to recognize each component's uses.

Sanitary Tee

White polypropylene PVC polymer female pipe tee connection on a white background

In drain setups, sanitary tees are T-shaped fittings. A sanitary tee is designed to direct liquid flow from a horizontal drain into a vertical drain.

Most people utilize the T shape to facilitate drainage because it works well for directing water downward while providing space for ventilation.

Sanitary tees are excellent for plumbing because they simplify removing obstructions by piping the region vertically. This makes unclogging a vent of blockages a breeze.


a PVC fitting - a draining wye pipe

A wye is used essentially the opposite way from how sanitary tees are used and has a little bend that makes it look like a lowercase Y.

These drainage fittings transfer waste from a vertical drain to a horizontal one. The tiny bend lessens the likelihood of clogging and allows the water to flow horizontally without creating much turbulence.

What Is The Difference Between A Sanitary Tee And Wye Pipe?

Plumbing wye and sanitary tee differ in a few ways, even though they are both sanitary fittings.

Let's classify them based on essential factors:


A sanitary tee has an upward angle of 90°, whereas the wye has a 45° vertical angle.


Compared to a wye, a sanitary tee is more flexible. The wye has several constraints when trying to fit it into small areas because it is less flexible than the sanitary tee.


A sanitary tee flows smoothly. This is due to the lack of any restriction points. Contrarily, there may be some wye restriction points. Water cannot flow freely at restriction points.

Large pipes in a particular location are accountable for this.


Installing a wye is more complex than installing a sanitary tee because cutting the wye in confined areas, such as under your kitchen sink, just to fit in is challenging.

On the other hand, a sanitary tee is much simpler; you can easily insert it into tight locations without cutting.


Both of these serve essentially the same function. Wastewater from toilets sinks, and other drainage systems are drained through it.

Both have a central pipe joined to as many pipes as you like that go to sinks, toilets, or any other drains you desire.

There is also potential for combination. A sanitary tee and wye are utilized when a separate drain pipe takes up too much room. But a new sanitary tee would suffice in these situations.


There could not be much difference when deciding the material to use for a plumbing wye or sanitary tee.

They are available in acrylonitrile butadiene styrene (ABS) plastic, carbon steel, cast iron, nickel, brass, stainless steel, etc., which are also frequently used materials.


In plumbing, a sanitary tee is used to connect two pipes. It features three openings: one on top and one at each end. Water or wastewater can pass through the top opening.

The additional two holes are for tying in pipes that divert water or wastewater from the mainline.

A wye is similar, except it features openings on both sides of a Y-shaped branch rather than one at the bottom. To put it simply, both have three holes. Due to their various forms, the holes' directions vary.


The cost of a sanitary tee or a wye depends on the size of the fixture. Generally, a wye is an expensive plumbing fixture, and the sanitary tee is cheaper.

Although the price of a wye is higher than a sanitary tee, they are still the most cost-effective polyvinyl chloride (PVC) piping components, costing between $1 and $5 per fixture.


One key characteristic that makes it possible to distinguish between wye and tee is its shape.

Sanitary tees will resemble the letter "T" when you look at their shapes, while plumbing wyes will resemble the letter "Y."

Space Required

Sanitary tees are adaptable and may easily squeeze into small places. However, the wye requires greater length and width than the sanitary tee but still can fit into small places.

How To Install A Sanitary Tee Or Wye Fittings

Collection of adjustable pipe wrench brass fittings water valve on wood board plumbing concept.

Basic plumbing expertise is necessary to install any multi-outlet drainage fitting, including sanitary tee and wye drains. Once you understand the fundamentals, installing this plumbing system is simple.

1. Measure And Mark The Pipes Needed To Cut

To indicate where it has to be cut, mark the area with duct tape. The tapes should be left on for 48 hours before being removed to ensure that any marks are still visible at that point, even if they eventually fade.

Click here to see this duct tape on Amazon.

2. Cut The Pipes

If possible, tighten the pipe's ends using an old wrench. This makes cutting simpler because the pipes won't be uneven afterward.

Ensure you have access to them before cutting if they are already set up directly beneath floor joists or ceiling beams.

Click here to see this wrench on Amazon.

Put the sanitary tee or wye fitting on a level surface, stabilize it by pressing your foot against one side, and tighten the other end with a wrench.

For quicker and straighter cuts, use a tubing cutter with two wheels. Leave the cuts slack at first, then tighten the pipe ends together.

Click here to see this tubing cutter on Amazon.

By doing this, you can avoid bending the pipes while using pliers that aren't meant to cut materials like PVC and ABS.

3. Install The Sanitary Tee Or Wye Fittings

When assembling fittings, it is simpler to use two wrenches for each side of the connecting point on the tee or fitting.

Keep them barely loose, then tighten them with both wrenches until all the parts are securely attached.

For a demonstration of using two wrenches, a video on YouTube is shown below:

For ease of usage and to avoid cracking, you can apply lubrication to the bolts, especially when working with plastics like PVC.

Click here to see this plumber’s grease on Amazon.

4. Install The Drain Lines

Before connecting it with pipes, use a second wrench to loosen up both sides of the sanitary tee, wye fitting, or other multi-outlet drainage fittings.

This will ensure no leaks when you put all the components together. Or else, you may need an expansion tank to prevent damage from excessive water pressure.

You should also consider whether the water pressure at the connecting point is sufficient. Maintain airtight connections wherever feasible to stop leaks.

A video tutorial on installing the fittings is shown on YouTube below:

Can You Use Sanitary Tees And Wyes Be Interchangeably?

Everything revolves around gravity and how the drainage system will function. When you utilize the incorrect fitting, you'll generate extra turbulence, which might result in clogs and undesired air vacuums.

This will make it more challenging to maintain and even harder to repair the system.

Misusing wyes or tees is a problem that many professional plumbers face. Repairers frequently visit homes to address the issue and provide the proper fitting.

After everything else has been put in place, adding the correct fitting needs a lot more work and can even necessitate the installation of new plumbing.

Which One Is Better: Sanitary Tees Or Wyes?

This is a sanitary tee used in plumbing drain system

Many factors must be considered when determining what kind of fixture to use.

The option you make will rely on your plumbing system, including how many branch lines are, how they are arranged, and how the pipes are aligned.

When you need a fixture that is simple to install and disconnect, a sanitary tee might be a smart option. However, you should know whether the present plumbing lines are vertical or horizontal.

The wye function is preferable if they are all vertical.

The wye may be the ideal choice if you need to connect multiple fixtures to one line or require a connecting point far from the source.

a PVC fitting - a draining wye pipe, angle 45

To Finish

May the discussion above help you distinguish the uses and differences between sanitary tee and wye so that you can have the right fittings for your plumbing system.

Since using them interchangeably will result in a tremendous mess.

Additionally, the plumbing authority has established rules and guidelines that outline the appropriate applications for different plumbing parts.

Made it to the end? Check out these related articles!

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