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Cantilevered floor

StephenInCalgary | Posted in Green Building Techniques on

Can all four sides of a floor be cantilevered? I want to attach 6 inches of rigid foam on the outside of the foundation ( basement) wall, and use a double stud wall above grade. The cantilever would simplify protecting the foam.

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  1. Expert Member


    Yes. It complicates the framing a bit though. On two sides you simply run the joists out. On the others you need a beam line set in, and the framing then goes the other way. You then have to deal with the point loads from headers and beams.

  2. brendanalbano | | #2

    Cantilevering all four sides of your floor is certainly doable.

    But why not avoid the issue of protecting exterior foam entirely and insulate your basement on the inside?

    Or at least consider reducing the cantilever by using an ICF and splitting the insulation between inside and out.

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