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Bathroom Plumbing Leak

jimmiem | Posted in General Discussion on April 26, 2013 06:50am

I have a water leak in a second floor bathroom which is showing up as a stain on the first floor ceiling directly below.  This bathroom is in a jog outside the main foot print of the house. The sink and shower are side-by-side on one side of the bathroom and the toilet is on the opposite side.  The leak is to the side of the toilet  toward the waste pipe that runs from this bathroom to the basement.  There had been a leak in this same location several years ago and I just assumed that the toilet wax ring had failed and I had a plumber replace it.  (Plumber did not confirm the wax ring was leaking). The ceiling stain was not dripping or soaking wet to the touch, then or now,  which has me wondering whether it is actually the toilet or water running along another pipe…..maybe from water that splashed out of the shower (stall with short curb) and made it’s way under the floor and ran along its waste pipe.  Does building code specify how the waste pipes are laid out under the bathroom floor?    If  I knew the waste pipes’ paths under the floor and tie-in to the main waste pipe I could narrow down the source of the leak.  The second floor joists, including the bathroom,  run from the center of the house.  The toilet doesn’t rock or move and has occasional minor condensation which the other toilets in the house also have.

Thoughts or suggestions appreciated

 

Thank you

        

Reply

Replies

  1. florida | Apr 26, 2013 08:16pm | #1

    The only way you'll ever know is ot cut a hole in the ceiling and see.

  2. DanH | Apr 26, 2013 09:01pm | #2

    Code only creates minimal limits on pipe routing, and even those limits may be violated in many cases.

    However, someone familiar with plumbing can make an educated guess.

    How old is this place?  Is the drain plumbing cast iron or plastic?  How solid is the bathroom floor?

    1. jimmiem | Apr 26, 2013 10:13pm | #3

      Plumbing Leak

      House is 25 years old.  All drain plumbing is PVC.  Bathroom floor is tile.  Subfloors are T&G 3/4 plywood.  If there is an underlayment between tile and subfloor then it is plywood.

      1. DanH | Apr 26, 2013 11:28pm | #4

        That makes a leaky joint unlikely (but not impossible -- sometimes the plumber actually forgot to glue the joints).

        A leak "following" a pipe horizontally would generally get no further than the first fitting of whatever type.

        If you posted a drawing of the layout (including wall positions, joist alignment, and the positions of known pipes) then someone could guess at the layout below.  Would only be a guess, though.

        1. jimmiem | Apr 27, 2013 07:39am | #5

          Plumbing Leak

          As the other poster suggested  I'll probably just cut a hole in the ceiling and that way I'll know for sure.  I would think that if the wax toilet seal is leaking then the ceiling would be continuously damp or wet.   

          1. calvin | Apr 27, 2013 07:46am | #6

            Jim

            If the wax ring is leaking, it might show up as dampness around the flange- if it's not grouted or tiled right up to the flange.  No patch, no paint-might be better to pull the toilet to find out.  Sometimes there's just not enough wax to complete the seal.  Fixes are stacking two rings, wax ring with funnel, or the newer style waxless ring.

            Of course, nothing beats the view from below.............

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