What size vent pipe should i use for a sewage vent in a new construction, and is there anything else I need?

Question

there are no code requirements, as such there is no plumbing/building inspector, this is a brand new house with two floors. the main bathroom sits right on top of the first floor bath with the laundry right next to it. its all pretty well packed together...

Answer 1

The sewage vent for a toilet or a sink is 2", one of the vents in the whole house must be at least 3". That being said , your code there can be different and not require the 3" vent. If you are just adding a new fixture use a 2" vent. That will work for sure.
Now, I do not know if you are connecting to an existing sewer line (main) or a branch, or what. The thing to know is never be farther than 5 feet from the vent to the fixture, and install a "p" trap on all fixtures except the toilet (its built in). A clean out must be installed so that the pipe can be cleared in case of blockage in the future.
Clean all joints well before cementing and always set up the whole thing (or as much as you can ) before you glue it. Use plenty of glue.
Good Luck

Answer 2

It depends on your local code and as mentioned previously, you should ask your local building department.

If you are referring to a stack vent, it should be a minimum of 3 or 4 inches (depending on local codes). This means that there should be a continuous pipe size from the main building drain up through the house and out the roof (good general plumbing practice). Off of both the stack vent and stack you will have branches that serve individual fixtures and bathroom groups. These will have varying drain and vent size depending on the method for installation (i.e. wet vent, dry vent, loop vent, etc.). There may be other roof vent penetrations that can ease installation when fixtures are far away from the main vent/stack and these can be smaller (however, due to frost and local codes, the smaller vents may have to be expanded right before penetrating the roof).

As to the other response mentioning the distance of the trap to the vent, it can be farther than 5 feet depending on what the size of the trap arm is (1-1/2, 2, 3, etc) and which code you look to (UPC, IPC, etc.). Generally speaking, the trap weir should not be higher than the top of the pipe down stream where it meets the vent pipe fitting.

Answer 3

There are a few different codes in use in the U.S. all of which require proper venting of the building drainage system. The code I am familiar with "the national standard" permits the fixture to be installed up to nine horizontal feet from the vent or re-vent. If you have no pipes exiting your roof there is a problem, but don't think the bathroom unvented because there is no vent penetrating above it. The problem you are having could very well be a simple one, call your local plumber before jumping to conclusions. I find it hard to believe the sub code official would miss the absence of a vent. Vent location and sizing are a big part of the rough inspection, and if there is one missing this would make the inspector and the township responsible for the repairs.

Answer 4

It depends on the load that you are placing on the drainage system. This is calculated in "fixture units" here is a link that will give you an idea of what you might need. http://www.metrokc.gov/health/plumbing/unitvalues.htm

I assume you are talking about 1 main vent servicing the whole building. In that case you would probably need a 3" vent. This varies from state to state and sometimes from county to county. I would recommend calling the plumbing inspector with the number of fixture units that you have with the fixtures you intend to install. The inspector will be able to give you an answer off the top of his head most likely.

Answer 5

No offense to answer one but VENT plumbing need not be 4 inches ID for a toilet that evacuates through that size plumbing. Certainly your issue should include finding out standards and CODES. No less than a 2 inch ID is usual for sewage/plumbing venting.

Answer 6

Most new construction requires a permit. Call and ask the Plumbing Inspector in your area.

Answer 7

11/2 inch for sinks, showers, 2 inch for toilets. there is a uniform plumbing code for all buildings in the USA

Answer 8

There isn't one correct answer because it depends on what part your venting and what the fixture loading on that part is. You should probably post a more detailed description or consult a professional.

Answer 9

Probably 4 inch, but you need to check the code in your area and adhere to what is written in the code.

Answer 10

The Main vent needs to be the same size as the main drain.................