broddo
New Member
Hi there! I'm in Ontario and I have an annoying situation. I'm doing a 2nd storey addition. My existing 3" stack is now located directly under a window on the new floor. This detail got missed by the architect. Moving the window at this point isn't really an option and space is pretty tight in that location anyway.
I've a couple of options - I'm just not sure which ones meet code.
Option 1: I can offset the stack in the floor. The photo illustrates this. You can see the top of the stack in the floor below the window. As space is tight, the vent portion would have to run horizontally for about 16 inches before going vertical. Then, when vertical, I would have to embed it in the 2x6 exterior wall which means notching that double top plate (could probably bore a hole but I don't know if this would be better). I don't know if code allows me to do this as the 3" OD is more than 50% the width of the stud.
So this option has two caveats: can I run the vent horizontally and can I cut into that support wall (maybe add some reinforcement)
Option 2: Don't vent the stack here at all - the attached photos illustrate this one. Instead add a 3" vent further upstream in the main bathroom ( works out about 6 foot away from the stack). The attached diagram illustrates my thinking here. This way, I don't have to worry about going through structural framing, however a portion of the vent probably has to go horizontal to get to where it needs to be.
Option 3: Do I need this 3" stack vent at all? If I properly vent every other fixture in the bathroom and connect them to a header in the attic before venting out the roof, would this work? The exit to the roof would have to be 3" anyway. The header could also be 3". I could also vent the stack using something smaller that wouldn't be so hard on the structural framing if that helped.
Can anyone tell me if any of these meet Canadian code and which option is best?
Many thanks!
I've a couple of options - I'm just not sure which ones meet code.
Option 1: I can offset the stack in the floor. The photo illustrates this. You can see the top of the stack in the floor below the window. As space is tight, the vent portion would have to run horizontally for about 16 inches before going vertical. Then, when vertical, I would have to embed it in the 2x6 exterior wall which means notching that double top plate (could probably bore a hole but I don't know if this would be better). I don't know if code allows me to do this as the 3" OD is more than 50% the width of the stud.
So this option has two caveats: can I run the vent horizontally and can I cut into that support wall (maybe add some reinforcement)
Option 2: Don't vent the stack here at all - the attached photos illustrate this one. Instead add a 3" vent further upstream in the main bathroom ( works out about 6 foot away from the stack). The attached diagram illustrates my thinking here. This way, I don't have to worry about going through structural framing, however a portion of the vent probably has to go horizontal to get to where it needs to be.
Option 3: Do I need this 3" stack vent at all? If I properly vent every other fixture in the bathroom and connect them to a header in the attic before venting out the roof, would this work? The exit to the roof would have to be 3" anyway. The header could also be 3". I could also vent the stack using something smaller that wouldn't be so hard on the structural framing if that helped.
Can anyone tell me if any of these meet Canadian code and which option is best?
Many thanks!