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InsightHorizon Digest

When would you use a sanitary tee

Author

Andrew Mccoy

Updated on April 12, 2026

A sanitary tee should be used when connecting a horizontal run, such as a waste arm to a vent stack or vertical riser. “If you think it’s expensive to hire a professional to do the job, wait until you hire an amateur.”

What is the difference between a sanitary tee and a regular tee?

A sanitary tee is a plumbing fixture that allows liquids to drain while also allowing the plumbing system to vent. The fitting resembles a normal tee fitting; the sanitary tee, however, when viewed from the side will have a definite downward sweep to the center inlet.

When would you use a double sanitary tee?

Double sanitary tees may be used when the barrel of the fitting is at least two (2) pipe sizes larger than the largest inlet.

What is a tee used for in plumbing?

A tee, the most common pipe fitting, is used to combine or divide fluid flow. Tees can connect pipes of different diameters or change the direction of a pipe run, or both. Available in a variety of materials, sizes and finishes, they may also be used to transport two-fluid mixtures.

What is a sanitary tee definition?

Sanitary Tee or “Tee” means a “T” shaped fitting that allows sewage to flow into the horizontal outlet pipe by entering through the lower end of a vertical pipe. A sanitary tee is a form of a baffle.

Can you stack sanitary tees?

You cannot use either one. You either stack two tees, which makes one drain lower than the other, or use the approved double fixture tee which is something about halfway between a cross and a double Y or double combination Y-1/8 bend, which is also illegal.

How can we reduce sanitary tee?

Slip the new sanitary tee in place, glue it to the drain going down. The 1 1/2″ piece sticking out of the top should just about touch the 1 1/2″ piece coming down from upstairs. Pull the tape and slide the Fernco down over the stub of 1 1/2″ pip out the top of the sanitary tee.

How far can a toilet be from a vent?

According to the UPC, the distance between your trap and the vent should be no more than 6 feet. In other words, for the vent to work properly, it needs to feed into the drain line within 6 feet of the trapways that connect to it.

What is PVC tee?

PVC tees are a fitting with three ends; two in a straight line and one on the side at a 90-degree angle. Tees allow a line to be split into two separate lines with a 90-degree connection. Also, tees can connect two lines into one main line. They are also often used for PVC structures.

Can you use a wye for venting?

Absolutely! Most any fitting is perfectly acceptable and legal, just don’t use any reducers, caps or traps in the venting.

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What does DWV pipe mean?

Older homes built before 1960 used galvanized steel or cast-iron pipes for drain/waste/vent (DWV) systems. DWV systems remove wastewater and prevent the flow of sewer gases into homes.

What is a swept tee?

A pipe tee in which each of the two branches gradually curves away from the main run of pipe instead of turning at a right angle.

What are the different types of sanitary fittings?

  • Hand wash basins.
  • Sinks (glazed or stainless-steel sinks)
  • Bath tubs.
  • Water closets.
  • Urinals.
  • Flushing cisterns.

Can a Fernco be used horizontally?

Under our code, we can use fernco’s where ever we feel, horizontal, vertical, diagonal, inverted, right side up, what ever you want to call it, we can use them there.

Can you tie shower drain into toilet drain?

Your shower drain can connect to the toilet drain, but it cannot connect to the toilet trap arm. This means that the shower connection will need to be made downstream from the toilet vent.

What does a sanitary tee look like?

A sanitary tee is shaped like the letter ‘T’, while a Wye is similar to ‘Y’. Sanitary tee is used for horizontal to vertical transition, and Wye is used for combining 2 lines into one horizontal line to maintain a flow without causing clogging.

Can a toilet and sink share the same drain?

In the US, with modern regulations, in most municipalities, yes, they do. The water and solids from your toilet waste line and the water from your drains end up in the same sewer line, if you have access to a municipal sewer system.

Does a toilet need a vent?

“Does a toilet need a vent?” And the answer is yes, your toilet has to have a vent. For more information on the great importance of plumbing vents, read our plumbing vent article here. And the size of this vent pipe depends on your local plumbing code.

What is a wet vent?

The official definition of a wet vent is a pipe that serves as a waste pipe and a vent at the same time. The wet vent also protects the drain’s trap for several fixtures, all connected to one system.

Can a plumbing vent have bends?

Changes in direction of vent piping shall be made by the appropriate use of approved fittings, and no such pipe shall be strained or bent.

What is a PVC saddle tee used for?

PVC saddles tees, also known as snap tees, are used to create a tee fitting for any section of rigid PVC pipe, without having to cut into the PVC pipe to install a traditional three-ended tee fitting.

What is street elbow used for?

A street elbow (sometimes called a street ell or service ell) is a type of plumbing or piping fitting intended to join a piece of pipe and another fitting at an angle.

What is a PVC bushing used for?

These bushings are used to connect two different size pipes and are available in a range of size combinations. They have a spigot fitting on the outside and a socket fitting on the inside. A socket x socket coupler is needed to connect the spigot side of the fitting to the existing pipe.

Can a toilet and shower share the same vent?

Wet vents are typically used when plumbing a bathroom group. So yes the shower can also be vented by the wet vent along with the toilet. There is one major stipulation when wet venting multiple fixtures when a toilet is one of them: the toilet must be the last fixture connected to the wet vent.

Can two toilets share one vent?

The waste lines can usually be tied into the same stack if the house has more than one toilet. They may need their own stack if they are on opposite sides. Two vent openings on the roof are needed since the stacks must be vented.

How do you vent a toilet without a vent?

Don’t worry if you do not have a vent pipe in your house, or if it is blocked and you can’t fix it. Instead of thinking about massive construction projects, you can use an Air Admittance Valve, well-known as a cheater vent. You may have heard that they are illegal and unreliable, but you shouldn’t believe every rumor.

Where do you put a long sweep elbow?

Long sweep elbows are commonly used in residential and commercial construction to direct water from above-floor drains and sumps to the main drain line. They are a kind of a very long (and curved) pipe fitting that is used instead of a 90-degree elbow fitting to route wastewater.

How far can a sink be from vent stack?

There is a vent between the sink P-trap and the point where the waste line goes to the main sewer. The vent can’t be more than 2 1/2 feet from the trap if the waste line has a diameter of 1 1/2 inches. The critical distance is 3 1/2 feet if the waste line is 1 1/2 inches.

What is coupling in plumbing?

In water and wastewater piping systems, pipe couplings are used to connect two or more sections of pipe with the aim of maintaining continuity between them. They can be used to join pipes of different or equal sizes, as well as connect more than just two pipes if they are cross or T-shaped.

What is the difference between PVC and DWV?

The only real difference is that DWV PVC is not made to handle pressurized uses like schedule 40 parts are. Instead, DWV pipe and fittings are made to handle a different class of uses – Drain, Waste, and Vent (hence the name DWV). … Another difference between DWV and standard PVC parts is the end types.

Can you glue PVC to DWV?

You can use a no-hub coupling–the rubber sleeve with 2 hose clamps. These come in slight variations depending on the materials they are intended to join, so make sure to get the right one.