Insulation on interior or exterior of frost wall - or both - for floating slab?
...foundation for a floating slab. The ~4' foundation walls sit on footings.Is it better to insulate on the inside or outside of the foundation walls, or both inside and outside? I’m wondering why you are going with a 4-foot-deep frost wall for a slab on grade. There are much cheaper and easier ways to build a frost prote...