Slab on Grade
Monolithic slab-on-grade foundations - Super insulated for LEED Homes & Passive House
...including monolithic slabs. Drains will go below the slab and insulation in the drainage stone; water lines can be placed there as well, or they can be embedded in the rigid insulation layer.
Running plumbing lines and drains in the drainage stone layer below a monolithic slab foundation
The ground below your slab w...