Ask Me Help Desk - Basement shower venting

Hi, I'm new here but a long time DIY'er. I'd like to know how would a basement shower drain be vented, when it is buried in the ground?

What I mean is what would be the standard connections? Would you use a wye after the drain trap, with the other outlet connected to the vent line, or should the vent line tee into the shower drain stack just below the concrete?

I've seen lots of pictures of doing it on a second floor system, where there's easy access, but I can't find anything showing a basement system.

Thanks... Randy

Quote:

Originally Posted by icandoit

Hi, I'm new here but a long time DIY'er. I'd like to know how would a basement shower drain be vented, when it is buried in the ground?

What I mean is what would be the standard connections? Would you use a wye after the drain trap, with the other outlet connected to the vent line, or should the vent line tee into the shower drain stack just below the concrete?

I've seen lots of pictures of doing it on a second floor system, where there's easy access, but I can't find anything showing a basement system.

Thanks...Randy

Hi Randy,

Would this be a floor drain that you are converting to a shower drain? If so,GOOD NEWS, it's already vented. If that's not the case clicl on back with more details. Like what do you mean by "buried in the ground"? Under cement? Under dirt? Cheers, Tom

Sorry Tom, guess I need to be more explicit, so here is the whole story along with some pics for reference.

I am remodeling my previously finished basement, which had a small, full bath... shower, sink and toilet. The shower was 30x30 with the sink at one end. I am removing the sink to enlarge the shower to a 32x48, one piece unit with a center drain.

The existing setup had a vent coming down from the upstaires bathroom, through a wall to the sink drain, and then through the slab where it ran over a couple feet and tied into the shower drain. I am assuming that this vent served both the shower and the sink... I guess that would make the previous shower vent a wet vent?

Now, I need to move the shower drain for the new shower and it just so happens that it will fall exactly over where the old sink drain line ran over to tie into the shower drain line at the wye.

So I will remove the existing shower trap, and cut the old sink drain and locate the new shower drain trap at that location, which leaves me with 1.) an open connection at the wye where the old shower drain trap was, and 2.) the need for a vent for the new shower drain.

Can I just connect the new vent line into that existing wye connection and reconnect to the vent line above as was done previously?

I hope this all makes sense.

Thanks for the help... Randy

The whole pic
Shower & sink drains
Wye connections
Vent connection
Old sink drain

Quote:

Originally Posted by icandoit

Sorry Tom, guess I need to be more explicit, so here is the whole story along with some pics for reference.

I am remodeling my previously finished basement, which had a small, full bath...shower, sink and toilet. The shower was 30x30 with the sink at one end. I am removing the sink to enlarge the shower to a 32x48, one piece unit with a center drain.

The existing setup had a vent coming down from the upstaires bathroom, through a wall to the sink drain, and then through the slab where it ran over a couple feet and tied into the shower drain. I am assuming that this vent served both the shower and the sink...I guess that would make the previous shower vent a wet vent??

Now, I need to move the shower drain for the new shower and it just so happens that it will fall exactly over where the old sink drain line ran over to tie into the shower drain line at the wye.

So I will remove the existing shower trap, and cut the old sink drain and locate the new shower drain trap at that location, which leaves me with 1.) an open connection at the wye where the old shower drain trap was, and 2.) the need for a vent for the new shower drain.

Can I just connect the new vent line into that existing wye connection and reconnect to the vent line above as was done previously?

I hope this all makes sense.

Thanks for the help...Randy

The whole pic
Shower & sink drains
Wye connections
Vent connection
Old sink drain

Hey Randy,

As I understand it you wish to eliminate the old lavatory drain and come off the wye to pick up the new shower. Then you want to come off the old shower drain and revent back up the old lavatory vent to vent the new shower. That works for me. Now what have you planned for the new lavatory drain and vent? Regards, Tom

Tom,

Sorry about taking so long to reply... been busy plumbing.

Anyway, thanks for the confirmation on what I wanted to do with the shower drain and vent. It's all done and is pretty much the same as it was when I started, except reversed, and now the vent line exits the slab in a different location to allow for a pocket door in the wall where it was previously located.

So I am now ready to fill in the holes and recement. What is the best material to use to backfill? I removed a lot of dirt and rocks, which I did save, but I have been told and have read several different ways to do this, i.e.. using sand, crushed gravel, etc. and someone told me to just use the same material I removed. What is standard practice in this area?

When I dug out the dirt around the old shower drain and the wye connections I found them encased in cement and had to chip it away to get it removed. Should I do the same thing now?

Do I need to add any reinforcement to the existing concrete prior to cementing?

Sorry for so many questions but this part is new to me and I don't want to have to do it over.

Thanks... Randy

Oh, by the way, I moved the lav sink out near the washer and tapped into the drain line for the washer for the sink drain... that part was easy. Previously, the laundry room and bathroom were separated by a wall, which is now removed. They will now share the same space.

Quote:

Originally Posted by icandoit

Tom,

Sorry about taking so long to reply...been busy plumbing.

Anyway, thanks for the confirmation on what I wanted to do with the shower drain and vent. It's all done and is pretty much the same as it was when I started, except reversed, and now the vent line exits the slab in a different location to allow for a pocket door in the wall where it was previously located.

So I am now ready to fill in the holes and recement. What is the best material to use to backfill? I removed a lot of dirt and rocks, which I did save, but I have been told and have read several different ways to do this, ie., using sand, crushed gravel, etc., and someone told me to just use the same material I removed. What is standard practice in this area?

When I dug out the dirt around the old shower drain and the wye connections I found them encased in cement and had to chip it away to get it removed. Should I do the same thing now?

Do I need to add any reinforcement to the existing concrete prior to cementing?

Sorry for so many questions but this part is new to me and I don't want to have to do it over.

Thanks...Randy

Oh, btw, I moved the lav sink out near the washer and tapped into the drain line for the washer for the sink drain...that part was easy. Previously, the laundry room and bathroom were separated by a wall, which is now removed. They will now share the same space.

Good morning Randy,

From what I see in your pictures you may use the same material you removed as fill dirt. You shouldn't have to add reinforcement to your cement patches.

You asked, "When I dug out the dirt around the old shower drain and the wye connections I found them encased in cement and had to chip it away to get it removed. Should I do the same thing now?"
I thought you were through and were cleaning up. When I find something buried in cement I cut back to a open area and install new.

Did you tie the lav drain into the washer drain ahead or behind the trap? And how are you venting it? Regards, Tom

Quote:

I thought you were through and were cleaning up.

I am. What I meant was I found all of the old connections, as well as the trap, encased in cement, which I have already removed to install the new plumbing. Should I now pour in cement around all of my new connections, and the new trap, as was done before?

Quote:

Did you tie the lav drain into the washer drain ahead or behind the trap? And how are you venting it?

Ok, I wasn't planning on going into detail about this, but you seem interested so I will. I'm probably going to regret this, but here goes.

I tied the lav sink drain into the same drain line as the washer, which are both tied into a vent up through the roof. Take a look at the simple schematic I drew up... not real professional but it should translate to you what I've done. The drain line sits on the foundation, which is about 12" high, and will be between two walls. This was all pretty much existing, I've just moved things around a bit to accommodate our plans.

There's about 5' between the washer and sink, and another 4' to the roof vent. I believe the vent distance is probably past the maximum allowed, but that's the best I could do with it. Running another vent through the second story is not a viable option right now. The shower and toilet drains are underground and tie into the main line somewhere down there.

So, what do you think? It probably wouldn't pass inspection, but I believe it will work. Do you see any safety issues with it?

Thanks... Randy

DWV Schematic