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A video question on below exterior door gap with exterior insulation

drewintoledo | Posted in Green Building Techniques on

How to fill the void below this door?  3″ roxul on each side.  Please see video –>

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  1. Expert Member


    That sill def. needs some type of structural support. It's only one refrigerator/dolly away from being torn off. Maybe a piece of C Channel back to the foundation? That would give you support up top, and a ledge for some type of stone /brick / whatever you want to put there.

    IMO that's one area door manufacturers will never come up to speed on. There really needs to be some sort of metal L type bracket that extends up into the framing of the door jamb on both sides for situations like this, so that the sill is self-supporting.

  2. Expert Member
  3. kyle_r | | #3

    Check out Erick Whetzel’s blog on this topic.

    1. Expert Member
      MALCOLM TAYLOR | | #4


      Yeah - if you are ever not sure whether you have thought through or been meticulous enough executing a task, looking at Eric's work will set you straight.

      1. kyle_r | | #5

        Agreed! I try to point anyone I can to Eric’s blog, especially if they are doing external mineral wool. Not only was he incredibly meticulous building his home, even better, he was incredibly meticulous documenting it.

    2. Expert Member

      I hadn't came across that blog before, it's great!

      I read through the door section, and I think he'd agree now on some sort of angle iron (fiberglass as he states), which in this case might as well be a C channel since it's being finished from below.

      "If I could do it over, I would use the fiberglass angle instead of the two 2×8’s. Last winter we had a cold spell for about two weeks where temperatures stayed in single digits, and although I checked behind my Rockwool in the basement just below my two door openings at the rim joists for any signs of moisture issues and found nothing (luckily), the fiberglass angle seems like a much simpler solution since it’s thermally broken and much smaller than my two 2×8’s, which would’ve meant I could’ve almost completely insulated below the door bucks while also giving this area plenty of long-term structural support."

      1. Expert Member
        MALCOLM TAYLOR | | #7


        One of the things I admire most about Eric is his clear-eyed appraisal of his work once he had seen how it performed.

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