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Looking for curbless shower floor in concrete slab details.

chuck77 | Posted in General Questions on

I’ve heard that builders take different approaches to dealing with the lowered area of the slab. Some form the depression intergal with the rest of the floor while others block it out and pour it later. I’m currently laying the underslab dwv system and building a box that will provide a void in the fill and EPS to install the p-trap and drain piece later at the correct height. Also, I hope the detail would show how the EPS is handled under the shower area. If using 2 layers of 2″ EPS are they both set down 2″ to maintain thickness of the foam and concrete? Thanks for any info on this.

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  1. GBA Editor
    Martin Holladay | | #1

    I found this one online.


  2. user-2890856 | | #2

    This is a very good system for well built and designed buildings .

    Check out the ADA ramp details for similar to curbless .

  3. CaseSensitive | | #3

    I would like to install a curbless shower in a new construction slab on grade barn. Is a shower pan necessary if 6,000 psi concrete (“waterproof”) was used as the finished floor for that room and shower floor. Rigid foam would be installed around the full perimeter and under the bathroom slab thermally isolating it, I plan to use in-floor heat, from the surrounding slab as well as providing a capillary break. I would run self adhering waterproof membrane up the framing on the inside of the room and down to the bottom of the slab meeting the slab vapor barrier. Thank you in advance.

    1. Expert Member
      Michael Maines | | #4

      There is a chance it would work ok but also a chance that the "waterproof" concrete is really "water resistant" and you would eventually have a mess on your hands. I would use a waterproof membrane system similar to what Martin shows in comment #1.

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