I want to install a bath room with toilet, tub/shower and sink in my unfinished basement.

There are three pipes combing from ground.
But there is not vent combing down from the basement roof.

Also, I have three contractors looked at my basement. I got confused with what they said.
The first one told me they can install new vent and the vent can go outside through sidewall.
The second one said that I do not need vent, just using wet vent and mechanical vent.
The third told me I have to install new vent starting from the roof of my house.

I kind of believe what they told me as they are experts.
Just want to know what is the best approach for the situation I have.

I live in Georgia.

Thanks.

--Michael

1)The first one told me they can install new vent and the vent can go outside through sidewall.

This can be done if local codes allow.

2)The second one said that I do not need vent, just using wet vent and mechanical vent.

It depends upon how the roughin was done as to whether anything was wet vented or not. A AAV, (Air Admittance Valve) may only be used with the express permission of the plumbing inspecter. Very shaky!

3)The third told me I have to install new vent starting from the roof of my house.

This is how it's uusually done, however, you may tie the new vent back to the main vent in the attic. This is called a "revent"


It would have been helpfulo if you had included the estimates for each one.

Regards, Tom

Hi, Tom

Thank you for your answer

Per your answer, it is possible to use wet vent. I am more intersted this approach.
Is there any specific requirement for roughin in order to use wet vent.


Regrading the estimate price, all would be a little over $3,000.

Thanks

--Michael

Let me show you a typical, (in my area) bathroom group rough in. This configuation only uses one vent for the entire group.
4" ,(under cement and basements) 3" (on first and second floor) from the toilet to the main. The lavatory to connect to the toilet drain line and vent to the roof or revent back in the attic to a existing roof vent. The tub/shower to connect to the lavatory drain line and be wet vented by it as will the toilet. Be advised to always check local codes before changing or remodeling your drainage system. Does this answer your question? Regards,k Tom

I would like make sure I understand the item 2)
2)The second one said that I do not need vent, just using wet vent and mechanical vent.

It depends upon how the roughin was done as to whether anything was wet vented or not.


But in your last statement, you say:
This configuation only uses one vent for the entire group.


As I do not have vent in my basement, I would like to know whether it is fine with building code to install bathroom without vent.

I live in Atlanta, GA.

Thanks.

--Michael

IF, and It's a big IF, your basement rough in is configured like the one I have put up then a single vent through the roof is all that's needed. If your code allows AAV's then a AAV may be used instead of a roof vent.
You ask, "As I do not have vent in my basement, I would like to know whether it is fine with building code to install bathroom without vent."
You MAY NOT install ANY fixture that's trapped without first venting it, either by a direct vent through the roof, a AAV if permitted or a wet vent.

"But in your last statement, you say:
This configuation only uses one vent for the entire group."

And so it does as far as a visible vent's concerned. The other fixtures are wet vented under the pour.

Regards and happy new year. Tom

Thanks Tom. The information you provide is very helpful.

I may use AAV to vent my basement as I read other forum saying AAV is fine with GA building code.

Further questions:
1. Where can I find buiding code for GA.
2. Should I apply working permit for basement bathroom
3. Should I hire an inspector to inspect the work to be done by the plumber or by myself.

Thanks.

--Michael

1. Where can I find buiding code for GA.
Call your local Building Department and ask for the local plumbing codes.
2. Should I apply working permit for basement bathroom
If a licensed plumber does the job, yes, a permit will be pulled. If you have confidence in your plumbing skills and do the work yourself then you may pull your own permit or not.
3. Should I hire an inspector to inspect the work to be done by the plumber or by myself.
If a permit's pulled the Plumbing Inspector will be sent out to inspect the job by the Buiulding Department at no additional cost.
Good luck on your project, Tom