1. pensfan84

    pensfan84 New Member

    Messages:
    32
    Location:
    Pittsburgh, PA
    Quick question for everyone -

    Am I able to stack vent a toilet and shower into a 4" ABS stack using a TY with a 2" inlet? Both the tub and the toilet are within 6' of the stack. Or should I branch drain the lav and tub and branch vent these above the highest fixture and tie into the vent stack? Thoughts?
  2. jadnashua

    jadnashua Retired Defense Industry Engineer xxx

    Messages:
    21,995
    Location:
    New England
    You can never reduce the size of the drain...a toilet needs to be at least 3", so running it into a 2" pipe is an instant source of clogs.
  3. nhmaster

    nhmaster Master Plumber

    Messages:
    3,189
    Location:
    S. Maine
    What does the stack serve?
  4. pensfan84

    pensfan84 New Member

    Messages:
    32
    Location:
    Pittsburgh, PA
    Sorry, I was not being clear. The stack is a 4" ABS. The TY would be 4", with a 2" inlet.

    The stack will serve two bathrooms, and that's all. A total of five fixtures - one tub, two toilets, two lavatory.
  5. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,615
    Location:
    Cave Creek, Arizona
    vent

    The proximity to a "stack" does not determine whether you need additional vents or not. WHAT the stack is being used for, and WHERE you make the connection, is what matters. Without seeing the job, we cannot tell you whether what you plan is doable or not.
  6. pensfan84

    pensfan84 New Member

    Messages:
    32
    Location:
    Pittsburgh, PA
    The stack is serving two bathrooms, and that's all. The connection would be made roughly 4' up the stack using a 4" TY with a 2" inlet. The connection is in the basement.

    The 4" TY will service a closet bend going to a toilet and the 2" inlet will service a tub.
  7. nhmaster

    nhmaster Master Plumber

    Messages:
    3,189
    Location:
    S. Maine
    serving what ? as drain or vent or both" Are the bathrooms on the same floor or on different floors? It makes a difference
  8. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,615
    Location:
    Cave Creek, Arizona
    stack

    That tells us NOTHING about where the various fixtures are located, but as soon as one other fixture flows past your connection, that stack is no longer a VENT for your new fixtures, and cannot be used as such, with a few exceptions.
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