New second floor bathroom: Drain design check

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by locus123, Oct 4, 2009.

  1. locus123

    locus123 New Member

    Sep 2, 2009
    I'm renovating my second floor bathroom, and wanted to have someone give me a yeah/hell no on my drain/vent design. I've spent most of the day trying to figure out how/when to vent, and I think I have it figured out, but "think" isn't good enough, I'm looking for a second opinion.

    So, it's a second floor bathroom and the main stack runs through a 2x6 wall in the corner.

    The bathtub/shower drain (tub is on the back wall with the stack behind it) will be maybe a foot away from the stack. I don't think I need a vent for this, correct? Just a p-trap connected to a sanitary tee (2" drain to 3" stack)?

    The toilet is beside the bathtub/shower, and the drain will have about a 3.5 ft run to the stack. Agan, I don't think a vent is required. Just a 90, 3.5' of ABS, then I'll use a 3" to 3" sanitary tee?

    The sink is farthest away from the stack, probably 6.5 ft. I'll run this drain inside the 2x6 studs about a foot off the floor. After the p-trap (within a foot or so), I'll run a vent up and across and join to my vertical vent (it runs beside the stack, then will tie into the stack in the attic). Again, sanitary tee?

    For connections, the order from the top of the stack will be: vent (tee), sink (tee), toilet (tee), bathtub/shower (tee), kitchen sink (wye).

    I read some places that the toilet couldn't connect higher than other fixtures, but I don't see a way around this, so I'm confused. Also, I'm slightly confused with when to use a wye and when to use a tee, but the above is what i could figure out. Any help is greatly appreciated, thanks in advance.
  2. dcelite

    dcelite Plumber

    Oct 5, 2009
    Los Gatos, CA
    1)Why does your tub tee have to be below the toilet tee?
    2) You can use a san tee (short sweep) when the drain pipe is going from horizontal to vertical. Vents don't require long sweep fittings, so, san tees are o.k.
    3) Remember to install your vent tee up above upside down.

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  4. hj

    hj Moderator & Master Plumber Staff Member

    Aug 31, 2004
    Cave Creek, Arizona

    Can you use a "side inlet sanitary tee" for the tub/shower? You cannot connect the toilet above the shower unless you vent the shower line. What did the building department say about your arrangement, and is this vertical pipe the "vent" from a downstairs bathroom?
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