Matt and Steve revisit the “slabless” slab in a 2017 zero-energy ranch home in Climate Zone 4B. Developed from an earlier assembly, this version demonstrates how field experience can improve design: adding smaller stone made the gravel base easier to level. The floor sits above grade on free-draining gravel, which provides a capillary break and supports water management. Matt and Steve discuss how wall insulation, cladding, and air-control strategies influence overall performance. They explain why air barriers require continuous sealing, while vapor-control layers can remain effective without perfect coverage. The episode also explores mold prevention and proportional insulation levels across foundations, walls, roofs, and windows, emphasizing the importance of adapting assemblies to site conditions and climate.