Melody
New Member
My basement is currently roughed in for an inlaw suite and a 2nd full bath. I would really appreciate some expert advise on if the current plumbing is correct. Please forgive me as I try to do the best I can to explain what is going on down there but plumbing is not something I am even going to pretend I understand! 
The main stack used to be cast iron and has been changed to 3" ABS. The path everything runs out of the house is to the right of the stack about 5 feet long and has a backflow valve around the center point of the run before it exits the house. Running about 12 feet to the left of the stack under the concrete is a 3" pipe that goes to the exterior wall and was capped off for future development upstairs. On that 3" pipe about 3 feet before the exterior wall a 2" pipe is teed off and runs about 5 feet then comes above the concrete into a wall to a Y that is shared by a sink and dishwasher. There is an AAV attached where the drain comes out of the wall at the sink before the p-trap. On the same 3" line under the concrete at 6 feet is another 2" pipe teed again running about 4 feet and comes above the concrete into a wall with another p-trap and to the right and top of the p-trap is another AAV on a pipe that exends up about 1.5 feet and then attached above the p-trap is a laundry box.
The small bathroom in the inlaw suite consists of a toilet, shower and sink. The toilet is about 4 feet from the main stack and is tied into it with a 3" pipe about a foot to the left of it. 2 feet prior to the toilet flange the pipe takes off to the right with a 2" pipe and runs about 4 feet to the shower, the shower has a p-trap as well. The sink is run directly off the stack with a 2" pipe about 1.5 feet above the concrete and runs about 2 feet to the right, then an AAV, then a p-trap.
The second bathroom is another 3" pipe teed from the main stack under the concrete. The tub is the furthest fixture away on the line at about 12 feet and it has a p-trap and then comes out of the concrete. At the 4 feet mark from the stack is the toilet that is tied in directly above the 3" pipe. The sink for that washroom is about 4 feet to the right of the tiolet and I can not really tell how that one is connected, only that a 2" pipe comes out of the floor into the wall with another AAV then a p-trap.
Everything drains perfectly fine so I am guessing the incline is run properly for everything. My biggest concern is venting. The AAV's are on all 3 sinks and the laundry but the other fixtures do not appear to be vented at all. They are only tied together with that one line under the concrete and no where in the walls or ceilings. Is this ok? I really do not know anything about plumbing so I am hoping someone can enlighten me with their knowledge and I thank you in advance. If you need more clarification on anything please let me know! (AAV's are permitted by code here in a renovation as a last resort)
Melody
The main stack used to be cast iron and has been changed to 3" ABS. The path everything runs out of the house is to the right of the stack about 5 feet long and has a backflow valve around the center point of the run before it exits the house. Running about 12 feet to the left of the stack under the concrete is a 3" pipe that goes to the exterior wall and was capped off for future development upstairs. On that 3" pipe about 3 feet before the exterior wall a 2" pipe is teed off and runs about 5 feet then comes above the concrete into a wall to a Y that is shared by a sink and dishwasher. There is an AAV attached where the drain comes out of the wall at the sink before the p-trap. On the same 3" line under the concrete at 6 feet is another 2" pipe teed again running about 4 feet and comes above the concrete into a wall with another p-trap and to the right and top of the p-trap is another AAV on a pipe that exends up about 1.5 feet and then attached above the p-trap is a laundry box.
The small bathroom in the inlaw suite consists of a toilet, shower and sink. The toilet is about 4 feet from the main stack and is tied into it with a 3" pipe about a foot to the left of it. 2 feet prior to the toilet flange the pipe takes off to the right with a 2" pipe and runs about 4 feet to the shower, the shower has a p-trap as well. The sink is run directly off the stack with a 2" pipe about 1.5 feet above the concrete and runs about 2 feet to the right, then an AAV, then a p-trap.
The second bathroom is another 3" pipe teed from the main stack under the concrete. The tub is the furthest fixture away on the line at about 12 feet and it has a p-trap and then comes out of the concrete. At the 4 feet mark from the stack is the toilet that is tied in directly above the 3" pipe. The sink for that washroom is about 4 feet to the right of the tiolet and I can not really tell how that one is connected, only that a 2" pipe comes out of the floor into the wall with another AAV then a p-trap.
Everything drains perfectly fine so I am guessing the incline is run properly for everything. My biggest concern is venting. The AAV's are on all 3 sinks and the laundry but the other fixtures do not appear to be vented at all. They are only tied together with that one line under the concrete and no where in the walls or ceilings. Is this ok? I really do not know anything about plumbing so I am hoping someone can enlighten me with their knowledge and I thank you in advance. If you need more clarification on anything please let me know! (AAV's are permitted by code here in a renovation as a last resort)
Melody
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