What is a wet vent?

So what is wet venting? Traditional wet venting is the venting of one or two bathroom groups. A bathroom group includes all the fixtures located within a bathroom, such as a water closet, lavatory, bathtub, shower or bidet. All these fixtures can be vented with a single dry vent.

What is the purpose of 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. For those that don’t already know, every fixture in your bathroom needs to be vented.

What should be the diameter of wet vent for four DFU or less?

2 INCHES
THE WET VENT MUST BE AT LEAST 2 INCHES IN SIZE FOR 4 DFU OR LESS, AND NOT LESS THAN 3 INCHES IN SIZE FOR 5 DFU OR MORE.

Where does the wet vent go in a bathroom?

The wet vent shall be considered the vent for the fixtures and shall extend from the connection of the dry vent along the direction of the flow in the drain pipe to the most downstream fixture drain connection to the horizontal branch drain. Only the fixtures within the bathroom groups shall connect to the wet-vented horizontal branch drain.

What’s the difference between dry and wet venting?

Dry venting is a simple system where each fixture has its own vent pipe. Wet venting is where one fixture’s vent is another fixture’s drain. This allows you to install several different fixtures in the same system of pipes, which is more complicated to set up, but uses fewer pipes.

Which is the last fixture in a wet vent system?

The most commonly added requirement is that the water closet must be the last fixture in the wet-vented system. That makes it difficult for a double bathroom group wet vent. The two water closets would have to tie in together. Actually, there is no technical justification for making the water closet the last fixture.

Do you need a water closet for a wet vent?

As simple as the wet-venting system is, plumbing codes often add unnecessary requirements. The most commonly added requirement is that the water closet must be the last fixture in the wet-vented system. That makes it difficult for a double bathroom group wet vent. The two water closets would have to tie in together.

What are the rules for a wet vent?

Wet Vent Rules. A wet vent can handle all the fixtures in two bathroom groups (a bathroom group is a lav, toilet, bidet, and tub or shower). To stay out of trouble with wet vents, go beyond code and use a 4-in. main horizontal waste line where possible. Any wet vents must be 2 in. minimum in diameter.

Which is the best example of wet venting?

Practical Examples: 1) Toilet and Sink: The toilet is vented through the sink drain. The toilet drain should be 3″, the sink drain is 1.5″, the shared sink drain/toilet vent area should be 2″, and the vent going up should be 1.5″.

Where is the wet vent in a shower?

The pipe downstream of the vent connection to the shower’s fixture drain and the connection to the toilet would be the wet vent.

Can a sink be used as a wet vent?

Wet venting is most common in conjunction with toilets and sinks; the drain for the sink is also the vent for the toilet. It can also be used for a variety of other applications but due to the following rules this is the most convenient and common situation to run into. Wet Venting Rules: