Slab on grade footings – interior vs exterior

Hello folks, I am building a new home in climate zone 4 (Marine, north of Seattle), slab on grade with R 20 below slab, 2×6″ R21 w/ R5 exterior insulationI have… Hello folks, I am building a new home in climate zone 4 (Marine, north of Seattle), slab on grade with R 20 below slab, 2×6″ R21 w/ R5 exterior insulationI have…Read MoreGreenBuildingAdvisor