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Slab-on-grade exterior threshold detail

Matt_Michaud | Posted in Green Building Techniques on

I am beginning a DER of an old commercial building – our new workshop – in zone 6, northern NH. The framed floor on piers is first being upgraded with poured footers, CMU stemwall, and a slab on grade. EPS will be beneath the slab and along the inside of the stemwall. The wall is a deep double stud with an air barrier paper on the inner wall. The gap in sill plates where the exterior door will go is a detail I am unsure of how finish. How should the 8″ block, 3″ EPS, and slab floor be flashed and sealed with the door frame and threshold? Euro-style window install details often say “doors are similar”, but I have never found a good diagram for this application.

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  1. Expert Member

    Where are you planning too situate the door? Is it an innie or an outie?

  2. Matt_Michaud | | #2

    Wall depth is 12" to 14" (game day decision). Windows will be in-betweenies for thermal performance and weather protection. I would be inclined to handle doors the same way, but it somewhat depends upon what the detailing options are.
    One idea I came up with last night would be to use a brushsweep seal on the door, shorten the block and EPS by 4", and pour a lightweight concrete (higher R) pad at the doorway. Even with lightweight concrete this is a themal bridge, but no additional threshold means rolling equipment in and out of the building would be simpler.

  3. STEPHEN SHEEHY | | #3

    In swing doors need to be innies and outswing, outies if you want the doors to open flat.

  4. Matt_Michaud | | #4

    Very good point (I feel foolish that didn't occur to me)! Exterior doors are outswing, so outies it is.

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