( basement inlaw apartment)
Can I run a waste line 30 feet from the sink to the waste/air stack.
I will be 5 feet from the wall then 90 deg turn for 20 feet along the wall, then 90 degree turn for 5 feet along the wall to the waste/air stack. I will be also adding another sink which will run 3 feet from the wall, turn 90 deg, for 6 feet, then turn 5 to the waste/air stack 1-1/2 pvc ( can I tap into this new feed)believe I need to run an air vent for this lenth also,

I can see a lot of clogs with all those 90's. Do you have enough room to give the line 7 1/2" of slope at 1/4" to the foot? If the first sink's already vented how will the second one be vented?
Back to you, Tom

I will start at approx 15 in height down to 7


At this time all I have to work with is the waste/vent stack that is roughed in by the builder of the house. The first sink is for the bathroom, approx 8 feet away and the kitchen will be 12 feet more away, 20 in all.
F

I have added an attachment to help visualize what I intend to do32305

In addition...

Put clean out on each 90 turn... Make that turn using Y+Street 45 instead of 90 Ell. Insert clean fitting into third , unused end of the Y.

In addition....

Put clean out on each 90 turn....Make that turn using Y+Street 45 instead of 90 Ell. Insert clean fitting into third , unused end of the Y.

Hi Milo,
I am guessing at the Kitchen (after the trap)will be Y for clean out-45 st for the turn to begin the 20 foot run.
The bathroom sink after the trap will be Y for clean out then-45 + Y into the 20 foot run.
The last corner will be tiled over as in a shower , so for this the Y clean out will need to be just after the toilet.
I think it is how I see it?
Did the air vent look OK
Otherwise I believe the advise is good.