Hi everyone,

I have come upon this site many times over the past few months for the wealth of knowledge here...now, I am in the midst of plumbing a bathroom for my basement, and am going in circles when it comes to the vents and drains. So, I will thank you in advance for any knowledge you can pass on.

First, the layout. It is a small bathroom that will have a sink, toilet and tub/shower....In that order as you enter the bathroom. All of these will dump into an ejector pit.

My plans are as follows (I will also provide a picture):

I was planning to use a 2" drain and vent at the sink, that will go into the floor (concrete) and join into the toilet line which will be 3". This will continue on until it picks up the shower/tub drain/vent also 2". Now I would really like to use 1 1/2" drains and vents for both the tub and the sink, but I think I read somewhere if you go into concrete it should be 2"??? 1 1/2" would be better, just because I have a 2x4 wall....I did not think ahead for a wet wall...I have some pictures here of generally what I am looking at:


The first one probably shows the most (with the writing on it).

Before I go too far...

1.Can I get away with using only two vents to vent everything? The total run from the sink to ejector pit will be about 6 feet, with the toilet in the middle?

2. Can the toilet drain be in the middle like I have it?

If I can get away with two vents, can they be 1 1/2" or must they be 2"?

In the picture with the writing, there is a blue line in the back where the tub and shower is. I was hoping I could somehow get a vent to go under the wall where it is already dug up, then up the back of the wall...That way when I run my water I will have fewer obstacles. Is there anyway this could be possible?

I will most likely have more questions, but for now I will leave it there, to make sure I am even in the ball park.