6. Integrated Roof Assemblies & Foundation Slab Interface
The roof is the envelope surface most exposed to winter heat loss and summer solar radiation, while the ground slab is the primary path for perimeter heat drain. SerVilla engineers an unbroken thermal jacket from the foundation perimeter up to the ridge cap.
Super-Insulated Roof Assemblies (U = 0.08 - 0.11 W/m²K]
- Cross-Laid Dual Insulation: 200 mm structural rafter infill rockwool crossed with 120 mm counter-batten insulation yields 320 mm of continuous insulation, driving roof U-values down to U = 0.09 W/m²K.
- Ventilated Counter-Batten Air Cavity: A continuous 50 mm cavity beneath the standing seam metal or tile roofing purges solar heat gain via buoyant convective airflow toward ridge vents.
- 10-12 Hour Thermal Decrement Delay: High-density rockwool creates an extensive thermal phase shift, preventing summer peak heat from penetrating living spaces during daytime hours.
Foundation Slab Edge Thermal Decoupling
- Perimeter XPS Thermal Skirting: High-density compressive XPS boards (100-150 mm, 300 kPa] encircle the exterior concrete footing, mating directly to the wall insulation without thermal gaps.
- EPDM Capillary Moisture Dam: A heavy-duty EPDM barrier is laid between the foundation concrete and the bottom steel track, stopping capillary rising moisture permanently.
- Seismic Anchor Detailing: Certified M12-M16 chemical concrete anchors lock the steel frame to the foundation, transferring high seismic shear and overturning moments to Eurocode 8.
SerVilla Engineering Note:
Details documented in this specification are engineered project-specifically based on local soil conditions, statutory climate data, wind/snow loads and chosen energy targets (PHI, KfW 40, Minergie). Certified execution drawings govern contracts.
