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Community and Q&A

Slab drop Front, Back and Garage Man Doors – Zero Entry Doors

idahobuild | Posted in General Questions on

Planning for future, when I start to find it difficult to travers steps and other obstacles, I am thinking of changing the slabs for the front porch, back patio and dwelling entry from the house to have no drop or step.  The garage door is certainly covered. Both the front and back doors have covered approaches (see atch’d).  As long as the slabs are slopped away from the house and the door/wall sills are WELL SEALED, any difficulties that I’m missing that might come from this change.  If the doors should/must be elevated above the slab, what is the minimum recommend/required.

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  1. Expert Member
    ARMANDO COBO | | #1

    I have designed houses with no step concrete for clients with mobility issues, and if you are going for a tight building envelope, you can install low-threshold or no-threshold doors, but you need to make sure your Bldg, Dept. allows it.
    Also, I usually design 12' min. deep porches, so there's small chance of rainwater getting in, but if you have less depth, you could install a fully drainable channel with a metal grate across and in front of the exterior patio doors.
    If you are required to drop the porch floor from the house finished floor, you can recess a door frame mold about 1" into the concrete, install a pan and set the door into it, then have your concrete contractor "build" you a tinny ramp to the bottom of the threshold.

  2. walta100 | | #2

    Some codes require the garage to be several inches lower than the living space. The idea being that gas fumes are heavier than air and keeping the garage lower keeps the explosive fumes out of the living space.

    1. Expert Member
      Michael Maines | | #3

      Walta, do you know of any codes the still require that? BOCA used to but I'm not aware of anyone using it anymore. It's not in the IRC and I've looked but haven't seen it in NFPA 101. I had heard the theory about gasses being heavier than air, but the dangerous gasses in a garage are all equal density or lighter than air. I have also heard that the step-down is in case gasoline leaks from the vehicle, or possibly for stormwater/meltwater. In any case, I'm not aware of current codes that require a step down.

  3. walta100 | | #4

    All I know is a few years ago when I was building my no step garage, the concrete sub told me that the near by county was still enforcing a garage step down requirement. True or not then or now I am not sure. A lot of places keep old code versions enforce for decades.

    My point is understand what your local people are enforcing before you pour concrete.


  4. Expert Member
    ARMANDO COBO | | #5

    Many moons ago, as far as I remember, we had that same code, but I believe it had to do with a vehicle stop when WHs and air handlers were installed exposed in the garage. We used to do small ramps for wheelchair accessibility. Then at some point, that requirement went away since we stop installing those appliances in the garage. They still require in a few local codes a 24" stand or bollards.
    If solar PV equipment and batteries are install in the wall were a car can hit them, our code requires bollards. Its better to install that equipment on a dedicated side area in the garage, avoiding vehicles all together.
    Optionally and occasionally, I've design 4"-6" step in large garages where the client wants to have tools and storage and don't want to have issues, then we'll install a small ramp for accessibility.

  5. idahobuild | | #6

    I think I'll just have a 2" drop to the various exists. I just don't know that it's worth complicating the building's details over. With any luck, I'll keep my physical capabilities 'til the end.

  6. plumb_bob | | #7

    There are tapered rubber mats that can act as small ramps into buildings, I have seen them spec'd for accessible residential units where the floor slab is higher than the porch floor.

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