Ground conditions come first
A foundation transfers building loads to the ground; its thermal behaviour also depends on connections to floors and walls. Energy performance alone cannot determine the foundation type. Geotechnical information, groundwater, terrain and structural loads are essential inputs. Houses with identical plans can require different foundations and water-protection arrangements on different plots.
Connect the insulation layers
Mark the heated volume on a foundation–wall–floor section. Façade, plinth and floor insulation meet here, and a gap near the slab edge creates an additional heat-flow path. Insulation carrying loads needs checks for strength, deformation and moisture exposure. Low thermal conductivity does not make a façade product suitable beneath a foundation. The thermal detail must remain compatible with the structural load path.
Coordinate water and penetrations
Surface-water management, waterproofing and drainage address different mechanisms. A drain needs a viable discharge point and maintenance access, not merely a pipe around the perimeter. Plan water and sewer penetrations before concreting and coordinate their seals with the protective layers. Correcting a misplaced penetration afterwards can damage work that has already been accepted or make the junction difficult to inspect.
Evidence before concealment
Agree sections, reinforcement drawings, levels and inspection stages before construction. Record the prepared base, insulation position and service routes while they are visible. Photographs help compare execution with drawings but cannot prove structural capacity. Bring geotechnical information and the house plan to the foundation discussion. A simplified wall-resistance calculation cannot replace the assessment of heat transfer through a ground-contact floor or the structural foundation design.