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Community and Q&A

Keeping water lines out of exterior walls

tupchurch | Posted in General Questions on

I am trying to design homes with water lines kept out of the exterior walls, but sometimes my love of windows draws an odd toilet or kitchen sink to the exterior. Do you think installing the water line in the side interior wall of a water closet or possibly bringing the kitchen sink water lines out vertically 6″ from the edge of the slab will help protect against freezing?

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  1. Expert Member
    DCcontrarian | | #1

    How are the pipes getting to the wall, through the floor or ceiling?

    If you have cabinetry below the sink you can run pipes in the toekick.

  2. Expert Member


    You have a few choices, all of which work fine:

    - Bring the waterlines up on interior walls.
    - Bring the lines up through the slab in close proximity to the fixture.
    - As DC said, use the kick space of your cabinets.
    - Bring them up in the exterior walls and insulate behind them with foam board.

  3. Expert Member
    Michael Maines | | #3

    It depends on the wall construction and your climate. I work mostly in climate zone 6 and use thick, heavily insulated walls; that way if I need to run plumbing in the wall, it's not a huge deal. If you're in a cold climate with 2x6 walls you can use foam insulation in individual bays to create service chases for plumbing.

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