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Community and Q&A

Incorrect plumbing joint fix for basement bathroom install

m2ew | Posted in GBA Pro Help on

5 years ago we had our main sewer line replaced with PVC line which 90s into our main 4″ stack. City and plumber failed to put in a 90 y / floor drain and we we’re told we would be fine with basement bathroom install. More recently, the driveway has been redone. Present day, 2 plumbers have told us that due to proximity of the joint to the wall, they cannot guarantee cracking will not happen on the short run of 4″ that goes out the straight out from the 90. There is an 8″ fail-safe as the pipe is under the foundation. However, if the cracking went past that we have cut and dig out a portion of the driveway to repair. While there is enough room to install a new 90 or 45 y and retie back into the main stack, we were told the only options are to put in a sewer pump or
sani-flush system to connect our toilet and shower (sink is tied in already higher in the stack). Are these our only options?

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  1. m2ew | | #1

    Here is a drawing of how the sewer line comes into the house. In prep, ground is currently exposed around the sewer line.

  2. GBA Editor
    Martin Holladay | | #2

    Your question is confusing (at least to me), but it sounds as if the problem boils down to the question of whether a new basement bathroom can drain to an existing sewer pipe by gravity, or whether a sewer pump is needed. Here's my reaction:

    1. You need to rely on the advice of local plumbers who have inspected your house. There is no reason to doubt their advice -- nor is there any reason to think that GBA readers, who have less information than the plumbers who have visited your house, will have a better grasp of the situation than these plumbers.

    2. This isn't really a green building question. There may be a plumbing forum on the web where you will receive better advice than you will here.

    Good luck.

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