I posted earlier in the week about some rough plumbing under the structural floor. I got under the plywood and found out there is no vent in the rough plumbing. I attached some pictures. The 1st picture is the rough plumbing and all 3 drains hook directly up to the main sewer line that goes to the street. The p trap in rough plumbing is a shower? Do any of them need a vent? The 2nd picture shows the main sewer line going in a Y. Going right in the second picture goes to the rough plumbing. Going left goes to the other side of the basement that has all the plumbing for the whole house. The pipe going up in the 3rd picture services the downstairs half bath and the p trape is for a drain for the water heater and furnace and a pvc pipe continues to the other side of the basement with a pipe going up into the wall for the master bathroom, kitchen, and laundry. I would like to put a bathroom on that same far side of the basement as far left (in 3rd picture but can't see all the way) that services the master bathroom, kitchen, and laundry. Can it be done?

1. Does the rough plumbing need a vent? I assume so but why isn't it there?
2. Can I hook up plumbing for a basement bathroom on the main sewer line that also connects to the master bathroom pipes?

I'm hoping I made this clear so someone that can help will understand. Is more information/pictures needed? Thanks for any help.

the first picture shows a trap and a vent for that trap. i can't really see too much more.
that vent may vent the toilet as well? it can be used the drain a lav and will then be a wet vent for the shower.

if you can make a drawing of your plumbing plan with drain, vents and sizing then any code violations usually can be seen by journeyman plumbers. current shower set up looks good with trap and vent.

Vents for "rough plumbing" would be ABOVE the floor, not below it, so they have not been installed yet.

Doug E., thanks for that info. I will try and get something drawn up.

So I just figured out from google and youtube that I have to use the vent from the second pipe which would be the sink. Correct? My question is when I build a vent from the sink pipe, where do I take it? I can't take it up through to the roof, or can I? Or do I go up into the ceiling of the basement and tie it into another vent that already goes into the roof?

Thanks



Edited 2 times.

either is acceptable.

Thanks Packy!

How do I find out what pipe is a vent? Does it matter how many sinks, toilets, and showers it services?

it is difficult to determine if a pipe is a drain or a vent if you can not trace it.
obviously if it is in a wall or in a ceiling that is above the highest fixture in the house, it is a vent.
if it is in a wall or ceiling and you have bathroom/s above, it could be a drain for something or it could be a vent for something below ????
there are limitations on fixures tied into a vent. i would not worry about overloading a vent in a single family home.

As long as it is REALLY a vent, and not a drain line.

If the pipe connects to a sink or other fixture in the basement, it is probably a vent, otherwise it is more likely to be a drain line.

Well, I thought I was getting somewhere. Although I've learned a lot with starring at the pipes, youtube, google, and bugging you guys. I checked all the pipes in the basement and they are all drain lines.

How in the world do I make a vent pipe?

If you see a stub pipe pointing down from the basement ceiling with a cap glued on it, it means the contractor left a "future vent" for the basement rough-in. It would be under an upstairs bathroom or kitchen probably.

I suggest you find a local plumber to run vents, drains, and waters.