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door threshold in a 12″ wall

user-917907 | Posted in Green Building Techniques on

What is the best way to build an exterior door threshold in a 12″ thick wall? The floor is concrete, with a 4″ gap of XPS between it and the 8″ thick foundation. The concrete floor is the same level as the top of the concrete foundation. The door will probably be in an “innie” position, that is, flush with the interior wall. There may be a storm door in the “outie” position.

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  1. RMGheHhbJx | | #1

    We build ICF all the time so we have addressed this quite a bit. It sounds like the threshold will cover up the foam if you set the door so it lines up normal toward the inside of the wall. If you were concerned about bugs etc you can etch the foam out approximately one inch and fill is with a cement type filler. We usually have "Thinset" around that works well and adheres fairly well. Setting the door toward the inside eliminated the problem of having the door swing resticted and trying to fit sheetrock back behind the hinges.
    At the exterior, either the siders or the stucco installers have no problem finishing into the door jamb. Save a few bucks and order the door without the brick molding. Also, we usually order a 6 9/16 jamb even though a 4 9/16" will work. It just seems like the extra two inches makes it easier to get a secure installation in most instances.
    As far as the concrete foundation showing, if it is under cover, the same thinset sticks really well and can be applied to be durable if the foundation at that location is fairly smooth
    . Many times though, we will use 6"-12" tile cut to width and just tile the strip over the foundation. We usually apply the thinset to allow us to tap the front edge of the tile slightly lower for drainage.

  2. Coyo | | #2

    Make it a single pour deal of your slab and be done with it - your thermal break of min 4" EPS sits under the door center and seals to your choice on the "Innie" :-)
    Email me if you're going ARCTIC wall - it evolved and is simplified on the latest detail. Best - TC

  3. user-651098 | | #3

    Can you explain the picture? Is the plastic wrapping the form lumber an extension of the vapour barrier from below the raft slab insulation? After the pour, do you cut the plastic or wrap it up the wall? Do you pour concrete into the space between the form and the insulation? Thanks, Jim

  4. user-917907 | | #4

    Tyson, thanks for the details of using Thinset and tile. I think those ideas will work well for me.

    Thorsten, I've emailed you for more information regarding your ARCTIC wall system.

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