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Second floor bathroom

| Posted in General Discussion on November 18, 2001 12:44pm

*
I have a seventy five year old house that I’d like to add a bathroom to. The second floor has a 6″ joist space. What space is required to put in the toilet plumbing? Is it OK to immediately turn 90 degrees below the closet flange and what distance is required to turn that 90 degrees? Any help would be appreciated

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  1. piffin_ | Nov 14, 2001 02:38am | #1

    *
    The bowl has its own trap so a ninety is OK. You might just make it but I usually look for 7"

    1. Hobie | Nov 15, 2001 09:02pm | #2

      *Thanks for the info. I am afraid I might have to raise the bathroom floor to get the space I need. If 7" is better, I won't have any fall in the pipe even if I make it in the 6" space. I have a 2-4' run before I can turn down. Your info will help me plan better though. Thanks again.

      1. piffin_ | Nov 16, 2001 07:15am | #3

        *Stop by the plumbing parts store and fit a few together to see how much space it takes up. You'd only need a 1/4" of fall for two feet.

        1. David_Thomas | Nov 16, 2001 08:24am | #4

          *As Piffin says, look for a toilet flange and 90 combination that has the tightest spacing. Specifically, you want a toilet flange that has a "spigot" (socket) tailpiece and a "Street 90" elbow. The street 90 is socket on one side and pipe-sized on the other. The pipe-sized end fits directly into the socket of the floor flange and is the tightest way to turn under the floor.You need 1/8" of drop per 1 foot of run, hence the 1/4" (for 2 feet) that Piffin mentioned. Flooring and floor finishing (tile?) may give you a bit more, depending on thickness. And if you absolutely need more height, it doesn't have to be the whole floor. You could just put in a 2' x 2' or even 18" x 18" area raised an inch or two right under the toilet.Hopefully you don't have to cut through any floor joists to route the drain line. Taking 3.5" or 4.5" out of a even a full size 2x6 doesn't leave much. Check with your building department if 3" drain lines are allowed. You save more than an inch that way.Get Peter Hemp's "Plumbing a House" by Taunton Press. Excellent for both professional plumbers and clever homeowners. The six diagrams on pages 102-104 of the different toilet drain/vent patterns are incredibly helpful for visualizing your options. You've got to get a 2-inch vent line into the run also and there are certain ways that that can be done. The patterns that Hemp illustrates show those details nicely. -David

          1. JohnD_ | Nov 17, 2001 01:08am | #5

            *"Wall Outlet" toilets exist. They mount on the floor, but the toilet flushes out the back. You mount a bracket on the wall, and bolt the toilet into it.A little silicone under the commode keeps it from rocking.Because of the room needed to make the turn, I had to move the toilet about 6 inches into the room. I put a little "knee wall" in. I put a top on it and it makes a nice shelf, and even looks pretty good.This is ESPECIALLY good when the waste pipe must go across the joists.[I also put in a wall hung residential toilet. THAT was another story, putting in a reinforced wall to hold the toilet.]

          2. Kevin_R._Craig | Nov 17, 2001 04:50am | #6

            *45 degree discharge floor flange with a street 45 will allow your toilet trap arm to run 4 feet in a 2 x 6 joist space, before you would have to turn down. Floor flange is made by Canplas.

          3. Kevin_R._Craig | Nov 18, 2001 12:44am | #7

            *45º Discharge Adjustable Closet Flanges Available in ABS or PVC with Metal or Plastic adjustable rings. Provides unlimited offset when used in conjunction with a Hub x Hub 45º Elbow. When used with a Spg x Hub 45º Elbow it provides a 2½" offset and the most shallow flange and bend combination available. Available in 4" x 3" and 4" x 4" sizes.

  2. Hobie | Nov 18, 2001 12:44am | #8

    *
    I have a seventy five year old house that I'd like to add a bathroom to. The second floor has a 6" joist space. What space is required to put in the toilet plumbing? Is it OK to immediately turn 90 degrees below the closet flange and what distance is required to turn that 90 degrees? Any help would be appreciated

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