Plumbing question: how close can wyes be?

[PCustoms]

Garage related, as I need to clean up the current mess of pvc and fernco before I can drywall the ceiling...

3" drain line.

Line runs parrallel to joist bay. Facing "downhill", line needs to hang a right as it nears the outside wall. Within the same joist bay, the toilet above needs to connect. Can I put a 90 connected direct to a wye without creating a consistently slow spot?

Only other option that comes to mind is running parallel pipes and then connecting farther down the line.

 

[Engineer61]

How much space do you have?
Definitely need to use at least a long sweep 90 like this, using 2 long sweep 45's with a couple inches of pipe in between would be better.

 

[Jackfre]

I would want to keep the WC tied into the run of the wye rather than the lateral and bring the vent off as closely as you can. As you are close to the wall, perhaps header of one floor joist and double up the adjoining to create the space. Seems a lot of work, but it is open right now and with the low flows today, you want it right under the floor.

 

[PCustoms]

Picking this project back up, does this look like it would work?

Only other option I can see is to tie the two pipes in further down the line.

 

[mcbane]

If it is going to be inspected you should use wyes with 45 elbow rather than sanitary tees.


Sent from my iPhone using Tapatalk

 

[PCustoms]

If it is going to be inspected you should use wyes with 45 elbow rather than sanitary tees.


Sent from my iPhone using Tapatalk

It won't be, but I did start questioning the difference/reason for the two today.

 

[mcbane]

In theory, a wye maintains water velocity so “solids” don’t get stranded in the main line just upstream of the junction. Very important for toilets.

I’m pretty sure a sanitary tee is only allowed where a horizontal drain pipe dumps into a vertical stack/vent pipe.


Sent from my iPhone using Tapatalk

 

[59 wagon man]

there is not really enough info to tell. a schematic of the bathroom would help and some codes require 4" for the toilet so you use a 4" x 3" closet ell

 

[PCustoms]

Damnit, was completely backwards in my thinking.

Thanks for the catch, guess it's back to HD tomorrow to swap out about 4 fittings.

 

[PCustoms]

there is not really enough info to tell. a schematic of the bathroom would help and some codes require 4" for the toilet so you use a 4" x 3" closet ell

Not sure what the code is around here, but trying to make best of existing mess. Existing toilet is 3", with a 3" vent (sole vent in system). Downstream is a sanitary tee for the sink. This whole mess cuts 45 across the joists, then drop down into a cluster of 4 way tee and fernco connecting toilet, kitchen, and shower (used to have jacuzzi too). Venting was horrible and I would get gurgling, so I added AAV in key spots.

Washer was rubber heater hose going to a green painted pipe under the porch.

Trying to get the toilet/sink/vent run pitched correctly and parallel to the joists, and then connect along the wall. In that pic intention would be to tie in to the 45. From ther, it's 37" to where I can add a 2" vent in a closet through the roof. Then the laundry sink/washer tie in (need to get a wye), then the shower (need to get a wye) before it dumps into the vertical stack.

I'll get a sketch tomorrow.

 

[gmwelder86]

You can put fittings as close together as they will fit. In your situation I would use a combo fitting which is essentially a wye with a 45 on it already or better roll a eye to a 45 and put a medium sweep on it to get your change of direction. Turns your 180 degree of change to 135 and at least in ca after 135 degrees of change it requires a clean out.

 

[PCustoms]

You can put fittings as close together as they will fit. In your situation I would use a combo fitting which is essentially a wye with a 45 on it already or better roll a eye to a 45 and put a medium sweep on it to get your change of direction. Turns your 180 degree of change to 135 and at least in ca after 135 degrees of change it requires a clean out.

Can't see it well in the picture, but the tee is rolled to the side and that is a 45 on it to match with the perpendicular pipe.

Heres a sketch. Above floor fixtures and traps omitted for clarity.

 

[PCustoms]

Well 2 wye back to back as shown in my last pic aren't going to line up to the existing pipe. Here's a couple more options that do fit.

I think the best option is the 1st pic, with a wye and clean out instead of the last 45. Would look like the 3rd pic, except the vertical wye and 45 combo let's me align to the centerline of existing pipe.