Is this combination legit?

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by Dan O., May 31, 2017.

  1. Dan O.

    Dan O. New Member

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    May 31, 2017
    Location:
    Monrovia, CA
    Forgive the primitive drawing:

    https://goo.gl/photos/PrJ1fRfGLcHLRoD29

    This represents a proposed abs w/c connection to a 4" sewer line where:
    • A - 4" street 90
    • B - Short 4" diam straight section
    • C - 4" san tee or low heel 90
    • D - 4" wye
    • E - 4" main line
    • G & F - w/c vent plumbed to main stack
    To be clear, A & B are running perpendicular to E, my main concern is whether or not C can be utilized leaned over as shown. Obviously the idea is to orient all the fittings so one doesn't slide off the w/c when attempting to use it; I mostly want to make sure I'm not missing something.
     
  2. Stuff

    Stuff Well-Known Member

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    Pennsylvania
    As long as C is less than 45º it is still considered vertical for most codes. Your inspector may have a different opinion. Do you have room to put a 45º between C and D to avoid the issue? A clean-out also might be asked for.
     
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  4. Dan O.

    Dan O. New Member

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    Stuff, thanks for the follow-up: I'm guessing you meant greater than 45º (as in closer to vertical), with E being appropriately sloped that would indeed put C closer to true vertical than 45º.

    Unfortunately, there's no room for an 1/8 bend between C and D, would not be able to get the w/c at floor level.

    Regarding your clean-out comment, this would be to access which section? Not shown is a clean-out within 3' of D, would access to A,B and C through the w/c not be considered sufficient?

    Making the first proposal work would be ideal but I do have an alternate approach here:

    https://goo.gl/photos/qtBiov5wekygUMUt8
    • A & D are now 4" combo tees and on the same plane as E
    • C, F & G are eliminated
    • Adequate (?) fixture venting is via the 4" main stack H
    Some additional notes:
    • Main stack H and the two 4" wyes below are present in the first proposal but were not shown for clarity.
    • With D being within 3' of the main stack I'm fairly certain the F and G were never needed for fixture venting in the first place, this was intended to replicate the originally installed vent arrangement which may have been overkill(?).
    • I'm not crazy about the second proposal because it results in more obstructions at crawl space level.
    • In both proposals section B is only long enough to dial-in the needed install distance between the w/c and the finish wall.
     
  5. Reach4

    Reach4 Well-Known Member

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    Location:
    IL
    Last edited: Jun 1, 2017
  6. Stuff

    Stuff Well-Known Member

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    Really need to see the whole setup before knowing what works. In the 2nd is H a vent or a drain? The 3' between H and D can't be a horizontal dry vent and if wet needs to be from the bathroom or adjacent, not anything else.
     
  7. Dan O.

    Dan O. New Member

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    Monrovia, CA
    Sorry Stuff,

    was distracted for a few days. I've drawn up a much better representation here that should leave nothing to the imagination:

    https://goo.gl/photos/88TaiuVhvYXaL3687

    This is a wet wall between a kitchen and small bath, single story home with crawl-space, 4 fixtures being served:
    • bathroom lavatory (A) vented directly through stack
    • w/c (D) w/2" vent tied to stack
    • kitchen sink (H1) w/1.5" vent tied to stack
    • tub/shower (H2) w/1.5" vent tied to stack
    Per your original response the arangement of F should be fine but the question of where a clean-out may be required remains. There is a clean-out at Y and I'm considering the inclusion of another that may be more conveniently accessed at X.
     
    Last edited: Jun 6, 2017
  8. Reach4

    Reach4 Well-Known Member

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    I suspect that my post about the closet elbow may have hurt your design. I was thinking you had a need to minimize the heights, but your pictorial made it clear that you do not have that need. I am not a plumber.

    There is no need for a santee for a toilet. I am not even sure it is permitted or desirable. The trap is part of the toilet, and the anti-siphon aspect of a santee is not needed for a toilet. The toilet trap siphons on purpose, but the trap gets refilled. I think your original plan for that area may be better.

    plumbing examples
    Plumbing-and-Trenching-for-Homeowners---2018 (klickitatcounty.org)
    http://www.co.lincoln.or.us/sites/d..._-_helpful_hints_residential_construction.pdf

    For your top santee being used as a vent, if you use that, then it goes upside down from the orientation it would be used with when connected to a trap arm.

    I suspect your plan could be simplified by taking advantage of the wet venting available for use with a bathroom group.

    You are certainly diligent in your planning.
     
    Last edited by a moderator: Sep 19, 2021
  9. Dan O.

    Dan O. New Member

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    May 31, 2017
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    Monrovia, CA
    Reach4-

    Height not an issue for the w/c but I am trying stay clear of a joist just ahead of D.

    Tell me more about the use of the 4" santee (F). I'd gladly employ a low heel 90 here but looks like I'll have to order it since it doesn't seem to be a commonly stocked item in these parts. Or am I missing the point entirely and you're saying the shown w/c vent is unecessary/undesireable?

    Comment on top santee B duly noted and I'll flip that so the 2" part sweeps down; shouldn't get strange looks from the inspector for that, right?

    Lastly, did some additional research and it looks like it would be a good idea to include some clean-outs for the sinks and tub/shower. Regarding clean-outs I'm still not sure the w/c is adequately addressed or how I can improve on what's shown.

    Thanks for links, checking those out now.
     
    Last edited: Jun 6, 2017
  10. Reach4

    Reach4 Well-Known Member

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    I don't know about using the "low heel". [​IMG]
    The usual way, from what I have seen, is to use a wye to combine the flows. Combining in the toilet waste downstream from other things seems to be a plus.

    I would not say extra vents are undesirable from a performance or permissions point of view.

    I would say that if you can somehow illustrate your joist that you are routing around, a plumber might offer a prescription.

    In your pictures, instead of using C (for example) 3 places, you could make the designations C1, C2, and C3. That way, if somebody with more knowledge wanted to comment, it would be simpler to refer to the particular fitting.
     
  11. Dan O.

    Dan O. New Member

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    May 31, 2017
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    Monrovia, CA
    I've updated the pic so every component has it's own unique designation:

    https://goo.gl/photos/88TaiuVhvYXaL3687

    Link in previous post has also been updated so it leads to the revised pic.

    Here's another view, looking at things from the kitchen side and showing the mentioned floor joist:

    https://goo.gl/photos/6tHwrT2w8ue7aRne8

    It's worth noting that the w/c plumbing is 4" from fixture to main line, the original arrangement was this size and so long as it's possible I'd like to avoid necking down to 3" at any point.

    Reach4 -

    I looked over the examples in the docs you linked to, I'm not comprehending why you're saying there's no need for santee F. Vent for the w/c also seems to be configured appropriately as far as I know. The 4"x2" low heel 90 I brought up would stand in for the shown 4" santee and be oriented with the 2" end serving as the vent; functionally I believe it would be no different than the santee, just harder to obtain. Obviously, the 4" santee needs a 4"-2" bushing (not shown) to accomodate the 2" 45 fitting.
     
  12. Reach4

    Reach4 Well-Known Member

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    Location:
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    I expect somebody with more knowledge will be able to give you good info.
     
  13. MACODEDOC

    MACODEDOC New Member

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    WHAT DID YOU USE TO DRAW THE PIPING ARRANGEMENT, NOT THE SINGLE LINE SKETCH BUT THE OTHER
     
  14. Dan O.

    Dan O. New Member

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    Last edited: Jun 7, 2017
  15. Stuff

    Stuff Well-Known Member

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    B1 needs to be upside down.
    As mentioned I to E1 is skipped most of the time as toilet is wet vented by lav. But since the next fixture down is the kitchen sink that may not be allowed.

    Are you able to run your plan past the inspector to get their opinion?
     
  16. Dan O.

    Dan O. New Member

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    May 31, 2017
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    Monrovia, CA
    Reach 4 pointed out the issue w/B1. Those three components for the w/c vent aren't gonna kill me so I'll leave those in, flip B1, add a cleanout for the kitchen sink and see what the inspector says.

    Thanks all for the help.
     
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