When water drains air must replace the space that was taken up by the water.
Vent stack thru roof.
Through traps all fixtures are connected to waste lines which in turn take the waste to a soil stack or soil vent pipe.
Plumbing vent pipes are connected to your drain system and are needed for water to drain properly.
If you can t put the main stack through the roof most local plumbing codes allow you to put it through a wall instead but there are conditions.
It also allows fresh air into the plumbing system to help water flow smoothly through the drain pipes however no water runs through the plumbing vent pipe.
Running a vent pipe out of the roof takes some careful preparation.
Increasing the vent opening to three inches just before it goes through the roof in frost prone areas is another precaution that prevents blockages.
At the building drain system s lowest point the drain waste vent is attached and rises usually inside a wall to and out of the roof.
All the vents connect to it through branch lines and it vents the main toilet the most important plumbing fixture in most houses.
The vent stack is the pipe leading to the main roof vent.
Vent pipes provide this air by running outside the structure of the house.
The main stack is the heart of the venting system.
The stack has to run the most direct route through open air or be ventilated to extend to open air.