Local building codes that regulate the materials used in the dwv system have changed over the years so most older homes have a combination of materials.
How does your bathroom sink drain and vent pipes work.
A note on the main drain.
Toilet vent option 2.
It also helps remove gas and odors common with a plumbing system allowing fresh air into the system to help keep the home smelling proper and to help water flow smoothly down the drain and out of the house.
A typical bathroom sink is a good example of how all these components work together.
If you hear gurgling sounds coming from your drains see standing water in your sink or bathtub or notice a slow drain in the bathroom or kitchen a blocked vent may be the issue.
A secondary stack perhaps 2 or 3 inches in diameter serves a branch of the system.
A plumbing vent or plumbing vent pipe is designed to regulate the air pressure throughout your plumbing system.
The horizontal vent pipe runs right next to the closet bend.
Examine the pipes under the sink.
Both kitchen 1 1 2 inches and bathroom 1 1 4 inches are smaller than the rest of the drain system on purpose.
When plumbing air vents or vent stacks do not work properly neither will your home s plumbing drainage system.
The centerpiece of a dwv system is the main stack usually a pipe 3 or 4 inches in diameter that runs straight up through the roof.
Vent stacks in a household plumbing system work the same way.
If the drain lines in your home have poor venting as in figure a for example water rushing down the drains will pull water from nearby p traps.
As water goes down a drain air is needed to equalize the pressure in the drain line.
If the toilet drain does not connect directly to a vent you must find another way to vent it.
It must be at least 1 1 2 inches in diameter.
If so note its size.
You can find your plumbing.
This is the purpose of a venting system.
You may be able to see the vent rising from the drain pipe.
If the drain line runs away from the wall where you want the vent use a reducing y and a 45 degree street elbow to point the vent line toward the wall.
When installing your vents it s highly recommended that you plan out your drain lines to minimize the risk of clogging.
Those vent pipes provide fresh air to all the plumbing fixtures so that the system can efficiently move water through the drainage pipes each time a sink is drained or a toilet is flushed.
They lead into larger branch drain pipes which lead into the 4 inch stack.