sub-floor wet vent

Discussion in 'Illinois Plumbing Code Questions' started by RehabJunkie, Aug 17, 2014.

  1. RehabJunkie

    RehabJunkie New Member

    Messages:
    2
    Terry:

    Thanks for the help, and advice you give on the forum. I've had to have failing cast iron replaced below the slab floor in a potential retail space. The actual "new" pipes were installed by a local licensed plumber. The state health inspector requested change on one item.

    The horizontal drain is 4". The vent, near the water closet, will be a wet vent (only from the lavatory). A wall cleanout (with cover) will be used. The criticism was that the vent/cleanout was 3", and code says cleanout at the end of the run must be the same size as the drain - 4". Therefore the cleanout at the base must be 4", (but can be reduced to 3" going on up the wall, and out the roof.)

    My question is:
    When changing the wye in the illustration below to 4x4x4, can the 90 degree at the base of the "wet" vent (lav only, no other fixtures) be a standard street 90, or does it have to be long sweep? Vents can be standard, but since this is technically a wet vent changing from vertical to horizontal, does it have to be long sweep? Wouldn't a long sweep 4" 90 be overkill for a lavatory?

    Thanks, Daniel

    Attached Files:

  2. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,825
    Location:
    Cave Creek, Arizona
    It would have to be a long sweep no matter what size it is. You do not show much of the installation, but I might use 2" and install a 4" floor clean out.
  3. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,825
    Location:
    Cave Creek, Arizona
    It would have to be a long sweep no matter what size it is. You do not show much of the installation, but I might use 2" and install a 4" floor clean out.
  4. Terry

    Terry Administrator Staff Member

    Messages:
    15,124
    Location:
    Bothell, Washington
    I would use a long sweep too. Then you know it will pass the next inspection.
  5. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,825
    Location:
    Cave Creek, Arizona
    It is the sink drain, so it would, or at least should, not pass inspection if anything but a long sweep elbow, regardless of the size.
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