sub slab insulation for pretty good house in CZ 3a
In the first stages of designing what I hope to be a pretty good house in climate zone 3A (a bit east of Raleigh NC). I have 3 questions.
Background: roughly 2k square foot 2 story house. Monolithic slab on grade. Finished concrete will be flooring downstairs.
1. Do you think adding R5 or R7.5 sub-slab insulation be worth it in terms of performance and comfort? Not required by code but mentioned in several articles (https://www.greenbuildingadvisor.com/article/determining-sub-slab-rigid-foam-thickness)
2. Detail for covered porches. Several parts of the house will have covered porches with concrete floor. I do want to insulate the slab edges with vertical insulation. Do you have ideas or details for areas where there is an adjacent slab for a porch. i.e. how do you thermally break the porch slab from the house slab?
3. Termites, ants, etc! Definitely a concern in my area. For the vertical perimeter foam insulation would you use termite treated foam of mineral wool? I don’t see builders in this area using mineral wool for slab insulation but the article seems like it has the right idea. (https://www.greenbuildingadvisor.com/article/if-ants-like-rigid-foam-should-we-stop-using-it)
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