Insulating a Slab Edge
mmorford
| Posted in General Questions on
I have a question about edge insulation for a single story, slab/frostwall home.
Location will be central Kansas (zone 4). I would like to use 1-2 inches of exterior foam in my walls, and am looking at 2×4 framing, as 2×6 + foam seems like more insulation than is necessary (considering budget constraints).
We are planning on using the slab as our finished floor.
The standard detail on GBA appears to have a notch in the frost wall to accommodate slab edge insulation, with the bottom plate overhanging the inside of the foundation wall slightly. My question- what would that detail look like for 2×4 framing?
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Replies
mmorford,
The detail can be problematic even with 2"x6" walls, as some codes do not allow the top of the stem walls to be reduced sufficiently to cover the foam. One way I can think of to make it work with 2"x4"s:
- Set the wall in so that the inner face of the framing is flush with the inside of the stem walls. The drywall and baseboard trim will cover the gap between the wall and slab. Use a cap flashing to cover the outside of the stem wall and extend out to the cladding.