I am finishing a basement on a newly built house. I noticed that the center of toilet drain will be 17 inches from the wall. I can’t move the wall closer to make it 13 inches because that would make the bathroom too small and the tub wouldn’t fit. So is my only option to move the toilet drain 4 inches closer to the wall?

You can see the far drain for the bathtub and the middle drain for the toilet. It's too far from the soon to be wall. Also the drain for the tub and the other drain for the sink wouldn't be in the wall. So I'm confused with how they laid out the drains.

enter image description here

Here's another photo of measurement if I move the wall to put the drains in the wall, which is what is intended. I'm short about 3 inches; I need 60 inches for the tub. Did my builder make a mistake?

enter image description here

  • 1
    Typically that represents planning for an interior insulated wall inside the concrete wall of the basement when making it "finished", but you've given few details, so not clear if it's even an outside wall.
    – Ecnerwal
    Commented Feb 24 at 2:30
  • 2
    A layout of the room would help us understand your challenges. You could just build a wall behind just the toilet. 2x4 and drywall is 4". It may look weird, but there isn't enough info to suggest more.
    – RMDman
    Commented Feb 24 at 2:33
  • 3
    are you sure those 2 stubs weren't intended to come up through the wall?
    – Tiger Guy
    Commented Feb 24 at 6:00
  • 3
    As asked by Tiger Guy, the drain stub outs were meant to be in a wall. Make the layout reflect that and your dimensions for the toilet will be correct. (What a difference a picture makes.)
    – RMDman
    Commented Feb 24 at 13:58
  • 1
    Whazzup with your "tub drain"? Are you planning to install tub on a raised platform? Tub drains are usually below floor level., tub drains in concrete are usually put in a below-grade formed box. Are you sure there's a trap below that stub-out?
    – kreemoweet
    Commented Feb 25 at 5:36

3 Answers 3


Your walls are in the wrong location.

My hunch is that both small pipes should be buried in a plumbing wall, and that maybe the wall at the other end is also out of position, which is why the space is too short for a standard tub.

Rough-ins usually don't include bathtub drains at precise locations. What you're seeing is probably the vent pipe for the circuit (shorter), which is inline with the drain pipe for the sink (taller). There may be a boxed out area for the bathtub drain nearby. Tap around on the slab to see if there's a thin spot. Sometimes the mason will smear right over the box with their power trowel.


One solution is to buy a toilet with a 14 inch rough in or a Toto toilet with their Unifit adapter, and buy the 14 inch adapter. This will put the back of the toilet 3 inches from the wall. Not ideal but depending on the constraints may be a good option for you. You could hide it with a pretty over-the-tank floor-standing shelf unit.

Caveat: it's not a cheap solution but probably cheaper than digging up the floor.

Other caveat: this answers the question but I agree with the comments that this isn't your biggest problem. If the tub is meant to be on a platform move the wall onto the pipes and get a shorter tub. If it's meant to be on the floor I don't see the necessary rough in.


There is no need to have a wall with zero clearance to the tank. That said, you can get toilets with extra-fat tanks that extend further to the rear of the drain center line. Or you could put in a clever little shelf unit in the extra space.

  • 1
    I've never seen an "extra fat" tank. All toilets are sized for 14", 12" or 10" offsets and generally use the same tank. Do you have an example?
    – isherwood
    Commented Mar 26 at 13:20

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