MattSkiWA
New Member
I have read enough of the plumbing code to guess how deep the rabbit hole goes and I'm up to my eyeballs. In pre-COVID days, I'd take my DIY plans down the local AHJ, ask questions, get feedback, and then go apply pipe cement. This week I called Terry, and he suggested I post here.
This bathroom is in an old ski lodge in King county Washington. The lodge has a building trap. During the winter season, the lodge is only heated on the weekends and the water is drained at the end of each weekend and a little antifreeze is poured into each trap. Existing plumbing is all ABS so we're sticking with that, in 4" and 2" sizes. The waste trunk is 4" to the toilets and 2" to everything else. The main vent stack is 4" ABS and there's a second 2" vent that serves only a kitchen hand washing sink. I intend to replace that sink vent with an AAV. The following drains drop through the bathrooms new concrete floor: 5 toilets, 1 waterless urinal, and 3 sinks. The floor itself is concrete sloped to 4 floor drains. There are two additional sink drains coming down from the kitchen immediately above the bathrooms. They drop through the bathroom inside the two strategically placed partition walls. The hand washing sink in the kitchen is the obligatory 1 DFU fixture plumbed in front of the waterless urinal.
Here's a layout of the bathroom:
The upper right corner is a combined shower, and urinal stall. The lower right corner is the accessible / family / caregiver stall, with a toilet, sink, and shower. Both rooms are waterproof so there's no shower surround (think: wet room). The entire bath room can be cleaned with a can of scrubbing bubbles and a garden hose. The showers are rarely used in ski season and the shower stalls will get some use as changing areas. In the fall, a smaller number of hikers use the lodge and the showers are used heavily.
Here is my plumbing layout:
The bottom and right are rough sawn 2x6 exterior walls, which will have snow against them for the duration of the winter. The walls are a bit under sized for the building height and snow load so there will be no hole drilling in the exterior walls. Along the bottom wall is the string of 5 toilets. The drain slopes toward the front of the building (top of the drawing) with the cleanout on the lower right edge (after string of lavs) being the highest point.
Inside the horizontal partition wall is a 2" drain from the AAV vented kitchen sink island and a 4" vent popping out the side of the building and ascending the outside wall. Inside the vertical partition wall is a 2" drain from the kitchen handwashing sink. It comes down inside that wall, runs across to the urinal, and then drops through the floor.
My questions:
Can I use a circuit vent (as shown, see also "circuit venting" below) for the string of toilets?
Can the circuit vent be 2 inch as shown in the IPC definition?
Can the leftmost lav be considered part of the circuit vent?
Upslope of the 5 toilets, a floor drain enters, then the circuit vent, and finally an AAV vented sink. The floor drain is within 6' of the circuit vent. Can it be vented by that circuit vent?
Thoughts, questions, and concerns? My twin goals are for this to work reliably for 50 years and to pass inspections without any rework.
Thanks in advance,
Matt
This bathroom is in an old ski lodge in King county Washington. The lodge has a building trap. During the winter season, the lodge is only heated on the weekends and the water is drained at the end of each weekend and a little antifreeze is poured into each trap. Existing plumbing is all ABS so we're sticking with that, in 4" and 2" sizes. The waste trunk is 4" to the toilets and 2" to everything else. The main vent stack is 4" ABS and there's a second 2" vent that serves only a kitchen hand washing sink. I intend to replace that sink vent with an AAV. The following drains drop through the bathrooms new concrete floor: 5 toilets, 1 waterless urinal, and 3 sinks. The floor itself is concrete sloped to 4 floor drains. There are two additional sink drains coming down from the kitchen immediately above the bathrooms. They drop through the bathroom inside the two strategically placed partition walls. The hand washing sink in the kitchen is the obligatory 1 DFU fixture plumbed in front of the waterless urinal.
Here's a layout of the bathroom:
The upper right corner is a combined shower, and urinal stall. The lower right corner is the accessible / family / caregiver stall, with a toilet, sink, and shower. Both rooms are waterproof so there's no shower surround (think: wet room). The entire bath room can be cleaned with a can of scrubbing bubbles and a garden hose. The showers are rarely used in ski season and the shower stalls will get some use as changing areas. In the fall, a smaller number of hikers use the lodge and the showers are used heavily.
Here is my plumbing layout:
The bottom and right are rough sawn 2x6 exterior walls, which will have snow against them for the duration of the winter. The walls are a bit under sized for the building height and snow load so there will be no hole drilling in the exterior walls. Along the bottom wall is the string of 5 toilets. The drain slopes toward the front of the building (top of the drawing) with the cleanout on the lower right edge (after string of lavs) being the highest point.
Inside the horizontal partition wall is a 2" drain from the AAV vented kitchen sink island and a 4" vent popping out the side of the building and ascending the outside wall. Inside the vertical partition wall is a 2" drain from the kitchen handwashing sink. It comes down inside that wall, runs across to the urinal, and then drops through the floor.
My questions:
Can I use a circuit vent (as shown, see also "circuit venting" below) for the string of toilets?
Can the circuit vent be 2 inch as shown in the IPC definition?
Can the leftmost lav be considered part of the circuit vent?
Upslope of the 5 toilets, a floor drain enters, then the circuit vent, and finally an AAV vented sink. The floor drain is within 6' of the circuit vent. Can it be vented by that circuit vent?
Thoughts, questions, and concerns? My twin goals are for this to work reliably for 50 years and to pass inspections without any rework.
Thanks in advance,
Matt
Last edited: