When asking for help is the only option - general grey-/black-/vent-layout.

[drunktrainpolka]

hello...

three story house with finished concrete floor basement. houghton county in michigan.

section A and below, 4" / above section A, 3" / hoping for 2" for venting (roof does have a 3" penetration).

1) where can i connect WC1? on section A? below/above section A on the vertical? on section A would be best for me. can't be 45 degrees but i can possibly get 15 degrees.

2) where can i connect WC2? on section B? below/above section B on the vertical? could WC2 connect straight down from where it's at - it's pretty much right above the stack.

3) where should the BT connection be?

4) where should the SK/LAB connection be? SK/LAV can only be connected between BT and stack. horizontal branch for BT and SK/LAV to stack - if so, where?

5) can my vent change from 3" to 2" or should i use 3" all the way?

6) with that where should i vent SK/LAB and BT?

the distance from BT to SK/LAV (with WC2 in between) is probably around 5'.

thanks in advance, kiko

PS - my condolences to terry's family and friends. while this is my first time posting, i have been coming here for years.

 

[wwhitney]

A couple general comments:

- In cold climates, you want the roof venet penetration to be 3" to reduce the risk of frost closure, and the 3" portion should extend from the roof outlet downwards until the vent is within the thermal envelope of the building (warm side of the insulation). So if that 2" horizontal run is on the cold side of the insulation, it really should be 3". If it's on the warm side of the insulation, then if you determine a 2" vent is sufficient (likely) and it would be a bear to run 3" horizontally there, you can use 2" and go back to 3" for the roof penetration.

- You've got fixtures on two different floors, I'll call them floors 1 and 2. That means you will need two separate stacks between floors 1 and 2, i.e. if you take a horizontal section of the system around the elevation where you wrote B, two vertical pipes will need to pass through that section. One stack will be the dry vent for fixtures on floor 1, the other stack will be the drain stack for fixtures on floor 2.

- No lav alongside WC1?

Cheers, Wayne

 

[Sponsor]

 

[drunktrainpolka]

A couple general comments:

- In cold climates, you want the roof venet penetration to be 3" to reduce the risk of frost closure, and the 3" portion should extend from the roof outlet downwards until the vent is within the thermal envelope of the building (warm side of the insulation). So if that 2" horizontal run is on the cold side of the insulation, it really should be 3". If it's on the warm side of the insulation, then if you determine a 2" vent is sufficient (likely) and it would be a bear to run 3" horizontally there, you can use 2" and go back to 3" for the roof penetration.

- You've got fixtures on two different floors, I'll call them floors 1 and 2. That means you will need two separate stacks between floors 1 and 2, i.e. if you take a horizontal section of the system around the elevation where you wrote B, two vertical pipes will need to pass through that section. One stack will be the dry vent for fixtures on floor 1, the other stack will be the drain stack for fixtures on floor 2.

- No lav alongside WC1?

Cheers, Wayne

wayne...

thanks for comments.

i do have a 3" penetration on the roof - i guess i shoulda have noted that. will try to edit my original post.

no lav near WC1 - using a tank top with a sink... as you flush the WC, water runs in a little sink for handwashing. that space is really a WC stall that you would find a school or airport or whatever public space.

i hear you on your second comment... boy. no way around that? WC1 is the only thing on that floor... could i get away with only one stack if i connected WC1 further down the 4" line?

thanks again, kiko

 

[wwhitney]

Since you're in Michigan, which uses the IPC, you could use an AAV for WC1. I have no experience on how well that would perform, a dry vent from floor 1 up to floor 2 is the conventional solution. There's no way for you to run a 2" or even 1-1/2" dry vent between floors? It can connect to your main stack at 6" above the flood rim level of all the 2nd floor fixtures.

Also, just to double check, the drawing show all the fixtures in the building? What about the kitchen sink, or a laundry? If they are on a separate stack that is separately vented through the roof and connects only in the basement, then I agree they can be ignored for this discussion.

Cheers, Wayne

 

[drunktrainpolka]

Since you're in Michigan, which uses the IPC, you could use an AAV for WC1. I have no experience on how well that would perform, a dry vent from floor 1 up to floor 2 is the conventional solution. There's no way for you to run a 2" or even 1-1/2" dry vent between floors? It can connect to your main stack at 6" above the flood rim level of all the 2nd floor fixtures.

Also, just to double check, the drawing show all the fixtures in the building? What about the kitchen sink, or a laundry? If they are on a separate stack that is separately vented through the roof and connects only in the basement, then I agree they can be ignored for this discussion.

Cheers, Wayne

wayne...

yeah, i can see about running a 2" vent between WC1 and the main stack. with that, does it make a difference where i attach WC1? it's really close to the main stack. how about WC2, BT, and SK/LAV? venting the SK/LAV is easy enough. but could the BT not be vented separately if using a santee close to the stack?

yeah, other fixtures (e.g., KS, DW, SP, LT) connect in the basement at a different location - and will most likely use AAVs for those. most likely, no. i will be using AAVs.

kiko

 

[wwhitney]

As to WC1, you can connect it to the stack you drew anywhere you want. You just need to connect a dry vent or an AAV to the WC1 fixture drain before that fixture drain hits the stack.

On the upstairs bathroom, that layout is best done via a floor plan. You can show the stack location on the floor plan as a circle, a horizontal section. The dry vent doesn't have to be directly over the vertical branch drain; if you want to wet vent everything with one dry vent connection, the typical way to do that is to dry vent the lav, and then use the lav drain to horizontally wet vent the tub and WC.

Cheers, Wayne

 

[drunktrainpolka]

As to WC1, you can connect it to the stack you drew anywhere you want. You just need to connect a dry vent or an AAV to the WC1 fixture drain before that fixture drain hits the stack.

On the upstairs bathroom, that layout is best done via a floor plan. You can show the stack location on the floor plan as a circle, a horizontal section. The dry vent doesn't have to be directly over the vertical branch drain; if you want to wet vent everything with one dry vent connection, the typical way to do that is to dry vent the lav, and then use the lav drain to horizontally wet vent the tub and WC.

Cheers, Wayne

wayne...

ok. here is the layout of the second floor bathroom with the main stack shown where it comes up and two places where it could up after segment/section B. the venting for the SK/LAV is not shown (it's trivial) just like the vent coming up from the WC1 in the floor below (for clarity).

i very much appreciate you taking the time.

kiko

 

[Jeff H Young]

I would expect you need a 3 inch vent anyway on the house so reducing vent to 2 inch as your only vent and then increasing to 3 might not be code.
for upstair bath wye off straight for the w/c on way to w/c another 3x2 wye pointed for the lav that will serve for vent on the w/c. then for b/t I would wye off 2 inch toward tub with a 2 inch long sweep under the wall and a 2x1.5 x1.5 santee looking at tub drain with trap at proper location vents tie back into the stack 42 inch minimum above floor continue 3 inch minmum out the roof increase to 4 if code requires for frost and snow

 

[drunktrainpolka]

I would expect you need a 3 inch vent anyway on the house so reducing vent to 2 inch as your only vent and then increasing to 3 might not be code.
for upstair bath wye off straight for the w/c on way to w/c another 3x2 wye pointed for the lav that will serve for vent on the w/c. then for b/t I would wye off 2 inch toward tub with a 2 inch long sweep under the wall and a 2x1.5 x1.5 santee looking at tub drain with trap at proper location vents tie back into the stack 42 inch minimum above floor continue 3 inch minmum out the roof increase to 4 if code requires for frost and snow

jeff...

thank you! see if i understood you correctly.

kiko

 

[wwhitney]

Your last drawing is fine, and can possibly be optimized in a few ways:

- The connection labeled "main vent" is completely unnecessary. You just need the dry vents for the tub and the lav, and they combine to go through the roof. The lav wet vents the WC.

- Jeff and I are under the UPC which would require a 3" vent for the whole house. But you are under the IPC, where a 2" vent for the house would suffice. So that top horizontal can now be 1.5", it's just an extension of the tub dry vent.

- The tub drain can stay 1.5" all the way to the lower 3" drain stack.

- The lav vent and drain could also be 1.5" under the IPC, although it seems like there's a benefit to keeping it 2" (as the UPC would require).

- If you don't want a drop in the tub drain where the vent comes off (which a san-tee and long sweep would give you), you can use an upright combo for the vent takeoff, so the drain outlet from the vent takeoff fitting is horizontal, rather than vertical.

Cheers, Wayne

 

[drunktrainpolka]

jeff/wayne...

thank you so much for the help. greatly appreciated.

kiko