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Supporting a door sill over exterior foam

ranson | Posted in General Questions on

I’m going to have 4″ of foam outside of my slab foundation. This means my door sill needs to stick out 4.5″ past the edge of my slab in order to cover the foam. I’m afraid that a heavy step by someone moving furniture will crack the sill in half if I don’t support it somehow.

Without introducing an egregious thermal bridge, how should I support the sill?



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  1. GBA Editor
    Martin Holladay | | #1

    This situation was discussed in a previous Q&A thread called Outie doors.

    You may also want to read an article called All About Doors.

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