This building system has become quite frequent in recent years. This flooring is laid on open porticos, namely floors built on a building's load-bearing pillars. Despite the fact that this building system is widely used, it gives rise to several problems, among which the major thermal dissipation and low temperatures that this type of floor is exposed to. Great attention is hence needed when building a structure like this and, in particular, excellent thermal insulation needs to be applied on the outer part of the building. Said insulation must also be highly resistant to compression, as it must bear a part of the structure's weight. Extruded polystyrene is the thermal insulation that ensures both characteristics and is appropriate for this type of application.

Laying: once the building's structure is erected on the portico, the X-FOAM^® WAFER insulation panels are applied directly on the portico after leveling the surface. The panels are glued on the support using cement-based adhesives. Therefore, the panels must have a rough or embossed surface: it is necessary to ensure the best possible gripping with the adhesive. It is also recommended to fasten the panels mechanically to the support. Once the insulating layer is fastened, it is coated with a layer of plaster reinforced with synthetic fiber or with a composite layer of smooth plaster reinforced with a fiberglass net and a plastic finish.