The venting for the plumbing should be above the highest drain-to-main-stack connection. The venting goes up – on a typical home it would vent out the roof. If you had the vents below then you may get water/sewage in them and your house would stink and possibly drains would not function as well.

Where do I put main vent stack?

It can attach directly behind the fixture or to the horizontal drain line. If two fixtures are on opposite sides of a wall, they can tie into the stack with a sanitary cross. This is called a common vent and can be found on back-to-back sinks.

Does main stack need to be vented?





At least one main vent stack is required for every building that has plumbing when connecting separately to the sewer for the building or its septic tank. The stack has to run the most direct route through open air or be ventilated to extend to open air.

How far can a toilet be from the main vent stack?

6 feet

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.

How do you vent a plumbing stack?

Quote from the video:
Quote from Youtube video: So the systems are always designed installed to be able one one inch plus or minus water column so that means the water level should move more than one inch.

Does plumbing vent go before or after trap?





The simple answer is if your trap from the fixture cannot see the vent then it is installed wrong. We must always keep the vent connection above the trap weir to prevent siphoning and keep proper pressures on both side of the trap.

Can a shower and toilet share a 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.

Does plumbing vent have to go through roof?

It does not have to go through the roof. From the plumbing code (I have the 2003 edition), P3103: It must not be less than 4 feet directly beneath a door, openable window or other air intake of the building or adjacent building.

How far should a vent stack be above the roof?

Unless a roof is to be used for any purpose other than weather protection, extensions of vent pipes through a roof should be terminated at least 12 inches above the roof. The vent should be extended at least seven feet above the roof if it is to be used for something other than weather protection.

How far can shower drain be from vent stack?



The maximum distance from a shower trap arm to a vent is usually 5 feet, though some municipalities may allow up to 8 feet.

How do you vent a main drain?

Quote from the video:
Quote from Youtube video: So that's a where the vent pipe actually connects to the main drain. System is right under the floor. Right here with a three by three Y. Okay let me show you a few other vent pipes.

How far does the vent have to be from the trap?

1 inch per foot = 83.3 mm/m.



P3105. 1 Distance of Trap From Vent.

SIZE OF TRAP (inches) SLOPE (inch per foot) DISTANCE FROM TRAP (feet)
11/4 1/4 5
11/2 1/4 6
2 1/4 8
3 1/8 12

What is the difference between a vent stack and a stack vent?



A vent stack is a vertical pipe that is only used for venting, and runs upward from the drain piping to the open air outside the home. Vent stacks are primary vents and accept connections from other vents in a plumbing system. A stack vent is used for both drainage and venting.

How far can a vent be from a sink?

Install the vent between the sink P-trap and the point where the waste line leading from the trap drops to the main sewer. If the waste line has a diameter of 1 1/4 inches, the vent can be no farther than 2 1/2 feet from the trap. If the waste line is 1 1/2 inches, this critical distance is 3 1/2 feet.

Can plumbing vent be below trap?

UPC 905.5 The vent pipe opening from a soil or waste pipe, except for water closets and similar fixtures, shall not be below the weir of the trap.

How high does a plumbing vent need to be?

The International Plumbing Code (IPC), requires plumbing vent pipes to extend vertically at least 152 mm (6 in.) above a roof, per Section 905.5, “Vent Connections and Grades.” Additionally, vent pipes must be at least 305 mm (12 in.) away from a vertical surface.

Does a plumbing vent have to be vertical?



Plumbing vents need to be straight on the vertical. This is necessary to avoid any vapor locks from occurring. When there is a bend in the vent pipe, moisture accumulates and is trapped.

Can you put an elbow in a vent pipe?

Note: You may have vent piping, but you still cannot use the tight 90-degree elbow — sometimes called a “vent elbow” — if the joint is below the water level, which is usually at the level of the sink.

How big does a vent stack need to be?

The minimum required diameter of stack vents and vent stacks shall be determined from the developed length and the total of drainage fixture units connected thereto in accordance with Table 906.1, but in no case shall the diameter be less than one-half the diameter of the drain served or less than 11/4 inches (32 mm).

Can vent stack run horizontally?

To answer your specific question, yes, vent pipes can have horizontal runs, as long as there is no possibility of them becoming plugged with water. In other words, any water that gets into the vent pipe opening must be able to run freely all the way to the sewer, without creating a “trap”.

Do you need a vent pipe for each toilet?



“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.