Wet Venting to Main Stack

[RobWilson]

Hi all!

I am planning on installing a bathroom in my basement, I live in Maine (IPC code, I think). I have easy access to the main stack to the septic system but venting the drains (one vent for a up flush toilet, one vent for a up flush sink, one vent for a large bathtub) is going to be difficult. After hours of research I am totally lost on when wet venting is allow.

My main stack is 4" PVC and I could tie a wet vent into the horizontal run right before the vertical drop that then goes through the wall to the septic tank. I posted a picture where the read line would be the wet vent. If that is allowed please let me know

Thanks a bunch guys!!
Rob

 

[John Gayewski]

You need one dry vent for your bathroom. They dry vent would connect to the wet vent (usually a lavatory).

The picture you have looks like it would just be a drain connection.

I'm not sure what your calling a wet vent.

To help you maybe a drawing or picture that has a proposed piping plan drawn over it.

 

[Sponsor]

 

[RobWilson]

Thank you for your reply! You have identified the crooks of my problem. Basically I don't have a dry vent so what I'm calling a "wet vent" is a drain connection with a pipe that goes upwards off the main stack before going back down to the up flush toilet/up flush sink/tub vent. I drew a picture as best I could... Which isn't great.

I think based on your answer to my other post (thanks running a new dry vent outside the house is my best bet. Better safe than sorry.

Thanks again!!

 

[Tuttles Revenge]

The new bathroom is above the basement. The basement is the floor the photo was taken looking at the main drain to sewer. A horizontal wet vent system can be made to drain all the bathroom fixtures using just the vent of the sink. But that vent can only go Up to connect to other vents or through the roof.

 

[RobWilson]

The new bathroom is above the basement. The basement is the floor the photo was taken looking at the main drain to sewer. A horizontal wet vent system can be made to drain all the bathroom fixtures using just the vent of the sink. But that vent can only go Up to connect to other vents or through the roof.


View attachment 96852

Nice drawing, that's very helpful The new bathroom is in the basement (should have said that) but either way the key here is that I definitely do need a dry vent from the roof for any bathroom.

There is this video on the Saniflow website (at minute 5:30) where they make it sound like you can vent the system without a roof vent. This is what made me think that was possible but I'm going to say now that's not a good idea.

Saniflow Wet Vent

 

[John Gayewski]

I don't suggest you make a bathroom like this. Generally a bathroom in a basement where the drain is higher than the basement will flow by gravity to a sewage ejection pump. All the fixtures flow into a pipe that flows to a pit. The pit is pumped.

 

[John Gayewski]

Also it looks like you have some other non plumbing approved piping down on the basement. You might want to either hire a plumber or do some more research on plumbing practices.

 

[Tuttles Revenge]

Yes, the layout for plumbing in the basement will be mostly the same, but the pump adds another level of complication. I prefer to install sumps with No penetrations through the lid. Saniflo makes a good system too if you don't want to get into digging up the slab.

 

[Jeff H Young]

yes you can pump a saniflo to where the red is you still need a vent though shouldnt be too hard .
there is some other odd ball plumbing in the picture no idea if thats connected or what ? it almost looks like a ptrap tieing into the main

 

[Reach4]

Is that 5-input drain manifold connected to the pipe going to the septic?

 

[Jeff H Young]

what are the hoses for ?

 

[RobWilson]

Yes, the layout for plumbing in the basement will be mostly the same, but the pump adds another level of complication. I prefer to install sumps with No penetrations through the lid. Saniflo makes a good system too if you don't want to get into digging up the slab.

Yeah using a Saniflo was what I was thinking to pump up from the basement bathroom into the main stack. I am definitely not interested in digging up the slab haha.

 

[RobWilson]

Is that 5-input drain manifold connected to the pipe going to the septic?

Yes that p-trap goes directly into the main stack to the septic tank. That clean out you see at the bottom is the straight line clean out to the septic tank.

Those pipes are a drain pipes for:
1). Water softener
2). Heat pump water heater condensation drain
3). Air sourced heat pump 1 condensation drain
4). Air sourced heat pump 2 condensation drain
5). Back washing sediment filter

Surprisingly enough those were installed by a professional plumber. I don't have a foundation drain so that was the solution. I have had the septic tank back up once before and since there is an air space over that middle port it backs up into the basement not the water softener etc. Basically this pipe acts as the lowest drain in the house so any back up goes through the air space at the top of that pipe into the basement.

 

[RobWilson]

what are the hoses for ?

Thanks for your response see my answer to Reach4 below

 

[John Gayewski]

Yes that p-trap goes directly into the main stack to the septic tank. That clean out you see at the bottom is the straight line clean out to the septic tank.

Those pipes are a drain pipes for:
1). Water softener
2). Heat pump water heater condensation drain
3). Air sourced heat pump 1 condensation drain
4). Air sourced heat pump 2 condensation drain
5). Back washing sediment filter

Surprisingly enough those were installed by a professional plumber. I don't have a foundation drain so that was the solution. I have had the septic tank back up once before and since there is an air space over that middle port it backs up into the basement not the water softener etc. Basically this pipe acts as the lowest drain in the house so any back up goes through the air space at the top of that pipe into the basement.

Those all need air gapped.