Plumbing a double vanity

Discussion in 'Plumbing Forum, Professional & DIY Advice' started by moose186, Nov 10, 2010.

  1. moose186

    moose186 New Member

    Messages:
    9
    Location:
    Midwest
    Hi-
    I'm doing a remodel and changing a single bathroom vanity to a double sink. I had planned on tapping off of the supply lines of sink #1 with a double valve, and running flexible SS braided lines from the valves to the faucets, directly above the supply lines to sink #1 and laterally to sink #2, about 3 feet away.

    At the the plumbing store, the owner said using a 48" braided line (need this length to give me some slack to go around some parts of the interior of the vanity) would be bad and prone to vibration and worse, bursting. So this is enough to freak me out.

    My options seem to be:

    1. open up the wall and try and run rigid supply lines to the second sink. Would look the best probably, but space is VERY tight in this wall with the waste/vent lines and I'm a novice solderer. Not sure I'd be able to put the supply lines coming out of the wall in the best positions- definitely not next to one another. It would also require me opening up the wall, which has been closed up and finished already. not a big deal to open it but...

    2. run rigid copper OUTSIDE of the wall, drilling some holes in the vanity inside walls to get over to the other sink. From there, run 12" or 16" braided SS flex lines to the faucets.

    3. stick to original plan if I misunderstood something from the plumber at the store (my wife went and was relaying this info).

    4. ?? any other options here? rolled copper?

    thanks very much in advance for your help.
  2. Redwood

    Redwood Master Plumber

    Messages:
    7,450
    Location:
    Connecticut
    Open the wall and do it right....
  3. Fubar411

    Fubar411 New Member

    Messages:
    141
    Location:
    St Louis, MO
    Is this on an exterior wall? I'm lazy, I'd be inclined to run the copper in the vanity if it was staying, if not put it in the wall.
  4. moose186

    moose186 New Member

    Messages:
    9
    Location:
    Midwest
    Fubar411- no, not an exterior wall. Vanity would stay, yeah.
    Redwood- I have minimal room to cut the 1/2 supply lines to tee off of it. Can't fit a hacksaw or rotating copper cutter tool. How do I cut the pipes? A Dremel? And if I hired a pro to do this, what would be a fair price?

    thanks guys for the help-
  5. moose186

    moose186 New Member

    Messages:
    9
    Location:
    Midwest
    Follow up with pictures, double vanity

    pic1.jpg

    pic2.jpg

    Here are pics of the job. The top photo with all copper shows a close up of the original area where I would have to T off the supply lines. The bottom 'after' image shows my work of getting the waste near the new sink with PVC, replacing that copper fitting in the top photo.

    1. Is the PVC work at least correct?
    2. And any help on how/where I could
    a. cut the lines with space at a minimum b. tap into the supply lines
    if I do this in the wall would be helpful for sure.

    Thanks very much...
  6. Redwood

    Redwood Master Plumber

    Messages:
    7,450
    Location:
    Connecticut
    The copper is the easy part I would heat up that elbow on the hot then replace it with a tee and street el then stub it out, then cut the cold put in a tee and stub that out.

    The fitting you chose is the wrong one and you have created a drain cleaners nightmare.
    A double fixture fitting should be used and those rubber couplings should be replaced with Fernco Proflex couplings designed for connecting copper to plastic. They have thicker rubber on one side to make up for the smaller outside diameter of the copper.
  7. moose186

    moose186 New Member

    Messages:
    9
    Location:
    Midwest
    Ah, thanks so much Redwood. The supply suggestions sound perfect. Will it matter that the stubs on sink #2 are so much lower than sink #1? Or is this just an aesthetic thing?

    So the double sanitary tee won't cut it? Need the double fixture tee?
    And those couplings I have on there are thicker on one side to make up for the smaller copper diameter. Both fit very snugly on both the PVC and copper pipes before even touching the clamps. I looked at the Fernco site and it looks like essentially the same product. Am I missing something?
  8. Redwood

    Redwood Master Plumber

    Messages:
    7,450
    Location:
    Connecticut
    The longer supplies are an aesthetic that will be hidden in the vanity. Braided stainless supplies are available in a few different lengths.

    The double fixture tee is what you want.

    The Proflex or, Mission coupling has a metal band which offers more support and will keep the connections straight. They are required under many codes for this reason.

    [​IMG]
  9. moose186

    moose186 New Member

    Messages:
    9
    Location:
    Midwest
    thanks again Redwood...all the help very much appreciated.
  10. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,882
    Location:
    Cave Creek, Arizona
    You need a "back to back" fixture fitting, NOT a sanitary cross or a double combination Y-1/8 bend, and the couplings are the improper ones. IF 48" supplies were bad, then using 60" ones for refrigerator icemakers would be a disaster, but we use them all the time. Flexible supplies "absorb" vibration, they do NOT cause it.
  11. moose186

    moose186 New Member

    Messages:
    9
    Location:
    Midwest
    HJ- I'm a little confused- is the 'back to back' fixture the SAME as the double fixture tee, or do you disagree with Redwood (implying that instead the double fixture tee is the same as the double combination Y-1/8 bend)?
    And are you saying the couplings in my photo are incorrect or the Proflex that Redwood said I should use is incorrect? In other words, do you agree that the Proflex is the correct coupling?

    And finally, you are saying that the 48" stainless braided would have been ok? (at this point, I need to open up the wall to fix the PVC work, so might as well tap into the rigid copper right there...)

    thanks HJ for your reply-
  12. moose186

    moose186 New Member

    Messages:
    9
    Location:
    Midwest
    last minute suggestions?

    On my way to the plumbing supply shop in the morning to get materials...any last minute comments from anyone?

    One quick question- is it going to be ok that my hot and cold stubs are going to be uneven? I'm not too concerned about the look of it as it will be within the vanity, but any technical issues?
  13. hj

    hj Moderator & Master Plumber Staff Member

    Messages:
    26,882
    Location:
    Cave Creek, Arizona
    It depends on semantics. Some consider a sanitary cross a "double fixture fitting", (which is it technically not, but would function as one), as opposed to a "back to back fixture fitting" which is neither a sanitary cross nor a double combination Y-1/8 bend, but is halfway between those two. The placement of hot and cold water lines is strictly a PERSONAL decision. You can put them anywhere you want to, or have to if there are conditions you have to work around. 48" supplies through the cabinets will work, they just look "klutzy" and unprofessional.
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