The core of the Tulppa panels is made from FINNFOAM, i.e., extruded polystyrene, which is a waterproof and mold-proof material with a high thermal insulation capacity. No bromine compounds or other environmental toxins are used in the production of FINNFOAM. The FINNFOAM material and Tulppa panels carry the M1 emission rating for best quality of indoor air. The surface of the panel is covered with a special-purpose cement mortar, which is reinforced with a fiberglass mesh. The panels can be attached on to all foundations.