A carriageable inverted roof, or parking roof, is an accessible flat roof designed to accommodate vehicle traffic. As in other inverted roof systems, the thermal insulation is positioned above the waterproofing membrane, but the roof build-up must also withstand the significant mechanical loads generated by the paving system, vehicles and operational use.
For this reason, the mechanical performance of both the insulation and the overlying load-distribution layers is a fundamental aspect of the design. Permanent loads, imposed loads and loads generated by vehicle traffic must be considered when defining the complete roof build-up.
Extruded polystyrene (XPS) is particularly suitable for this application because it combines low water absorption with high compressive strength. X-FOAM® HBT 500, with a compressive strength of ≥ 500 kPa, provides a high mechanical performance for carriageable inverted-roof applications. Where even greater compressive strength is required by the project, X-FOAM® HBT 700, with ≥ 700 kPa, provides an additional option.
Above the XPS insulation, the roof build-up incorporates appropriately designed layers that distribute the loads generated at the finished surface over a larger area of the insulation. The complete paving and load-distribution system must therefore be dimensioned according to the expected traffic, loads and structural requirements of the project.
