Hmm. My bathroom was roughed-in with the drain lines for the shower, toilet and sink already in place and piped into the sewage basin.

> There is already a vent pipe above that I can run down to the basin, I’m just wondering if this will vent the shower and toilet properly.

You should be able to extend the utility basin vent pipe to the sewage basin if that vent pipe exits through the roof to the outdoors. Note that a Studor Vent or other mechanical vent cannot be used with a sewage basin.

> It sounds like this is what you did, and there are no other vents already run, so I think this will work. What do you think?

Make a sketch of what you plan to do. Call your local Building Dept. and ask for a visit by an Building Inspector. You don’t need a building permit to ask for a visit. Show him what you plan to do and ask if it will meet code. The Inspector won’t design it for you, but will tell you if it’s flawed and what would be needed to meet code. I arranged for a visit by a Building Inspector before I started my project and pulled a permit. The Inspector was really great and shared interesting details about my neighborhood.

Thanks for the response. I’m about to add a bathroom to my basement and the only thing I’m not clear about is the venting. I have a set up very similar to yours except I just have one pipe running underground to the basin. It hasn’t been stubbed up yet, just a hole in the cement with a capped pipe. I think I’m going to cut up the cement and run two more pipes, one for a shower and the other for the sink, and put the toilet over the current hole.

The utility room has the basin, it’s about ten feet from where the bathroom will be. There is already a vent pipe above that I can run down to the basin, I’m just wondering if this will vent the shower and toilet properly. I could then install the Studor Mini Vent for the sink. It sounds like this is what you did, and there are no other vents already run, so I think this will work. What do you think?

The bathroom sink is vented by a Studor Mini Vent as detailed in Part 13 of the project. A Studor Mini Vent is a one-way mechanical air valve, it let’s fresh air in, but blocks sewer gases from escaping into the room. I noticed that most of the bathroom sinks in my home have Studor Vents that were installed by the home builder.

This vent configuration complies with the Building Codes in my area. The Building Inspector looked under the bathroom sink to be sure the Studor Mini Vent was installed before he signed off on my permit.

The basement bathroom has worked well and I’ve never experienced problems with traps being siphoned dry, gurgling or other issues.

Thanks for asking!
Bob Jackson

How did you vent your bathroom fixtures (sink, toilet, shower). I don’t see any vent lines running to the fixtures. Only the vent line for the ejector pump. Were the vent lines already run???

You have to make a cut from the edge of the grommet to the hole for the cord. To insert the cord, spread the cut with your fingers and slide the cord in sideways. I know this sounds a bit worrisome, however the grommet is squeezed together when it’s installed in the basin cover making everything airtight.

In my situation, the grommet for the electrical cords has three holes:
1) Float switch cord
2) Pump cord
3) High water alarm wire

I had to make two cuts in the grommet:
(1) Outside edge to Float Switch
(2) Float Switch to Pump Cord (connect the dots).

No cut was needed for the high water alarm cord because the end that attaches to the alarm and doesn’t have a plug.

Take care,
Bob Jackson