Extruded rigid polystyrene foams (XPS) from BASF, Styrodur 5000 CS, Styrodur 4000 CS and Styrodur 3035 CS has received technical approval to be used as multiple layers in order to provide an external insulation in groundwater from the Deutsches Institut für Bautechnik (DIBt) and the German Institute for Construction Technology located in Berlin.
Earlier, XPS single layers were approved for perimeter insulation. So far, the XPS boards have been utilized as multiple layers of external insulation for structural components having contact with the ground.
The new approval allows construction companies to use insulating materials for construction works, while meeting the strict energy needs imposed on new buildings. Now, BASF received DIBt approvals to use Styrodur C multiple layers for inverted roofs, perimeter insulation, and foundation slabs.
Perimeter insulation decreases heat dissipation at a building’s bottom. Since Styrodur C has skin on two sides and a closed cell foam pattern, it demonstrates minimal water absorption and high compressive strength properties, which make it a suitable material for perimeter insulation.
Styrodur C can be submerged to 3.5 m depth in groundwater. A maximum of three layers of insulating material having 400 mm of total thickness can now be utilized on basement walls and under non-load-bearing foundation slabs. The XPS boards tightly placed and packed to bond in perimeter insulation. Boards having a rabbet edge must only be used and the single layers must be aligned to sheath joints.
For more than four decades, homes have been protected from moisture, cold and heat by the rot-proof, water-repellant and pressure-resistant Styrodur C. It extends the lifespan and value of buildings and enhances the living conditions. The several Styrodur C grades, whose cell gas is air, vary mainly in their compressive strength.