Basement toilet install tie in to cast iron, venting?

Users who are viewing this thread

Rob W.

New Member
Messages
4
Reaction score
0
Points
1
Location
Seattle, WA
I'm working on installing a toilet in the basement of my 1950 home in Seattle. I've broken out most of the concrete around the old floor drain, which I don't need any more (it used to drain the utility/laundry sink, but I've since connected that to the stack with the black ABS you can see on the left. I'm planning on just getting rid of the floor drain in the center, and installing the toilet flange just to right of it (near the red trowel). I'm thinking I'll connect in to the main line (the black cast iron, still slightly under the concrete) with an PVC wye and some no-hub Fernco adaptors. My question is, do I need the vent pipe that's currently dropping down at an angle to pick up the floor drain? Should I drop it straight down on to the main line with T connection to increase the venting for the second toilet? Thanks for any advice!

basement plumbing.jpg
 

Terry

The Plumbing Wizard
Staff member
Messages
29,946
Reaction score
3,460
Points
113
Location
Bothell, Washington
Website
terrylove.com
In this case the toilet should get it's own vent before entering the main line there. I would consider redoing the piping for the sink while you are at it and make it more direct with fewer changes of direction.
Without a vent, any toilet flushing upstairs is going to upset the water in the downstairs bowl.

For the shield couplings, Mission and Fernco make them, make sure the side going to the cast is the right dimension. Old cast is not the same diameter of the plastic pipes. They make these couplings with differing sizing for that purpose.

You might frame in a half or full wall by the toilet to hide the vent.
 

Rob W.

New Member
Messages
4
Reaction score
0
Points
1
Location
Seattle, WA
Thanks, Terry. So could I bring the toilet drain towards the main line, and before it gets there, tie in to the existing vertical vent pipe? (center pipe on the picture.) This is the vent stack shared by the 3 sinks and shower in the house; it is not the integrated vent for the upstairs toilet. Would that be ok? Great idea on building a wall to cover that stuff; I think I've got room. Thought about re-doing the utility sink as you suggest, but worried about cutting into the vertical cast iron and having the whole stack pull down and mess up everything upstairs...
 

Terry

The Plumbing Wizard
Staff member
Messages
29,946
Reaction score
3,460
Points
113
Location
Bothell, Washington
Website
terrylove.com
In the picture below I show how the downstairs vent goes up and ties in on the second floor at 42".
Vents make their way up and waste finds it's way down.

dwv_b2.jpg
 
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks