FI75384C - PAO MARKEN BELAEGEN GOLVKONSTRUKTION. - Google Patents

Description

ι 75384

Underground floor structure

The invention relates to an underground floor structure with a porous ventilation layer against the ground surface, which is specially intended for the ventilation of radon gas and which is connected to the outside air surrounding the building; at least one thermal insulation layer superimposed on the ventilation layer; and a concrete layer cast on top of the thermal insulation layer (s).

It is known to ventilate unhealthy radon gas from under the floor, either by means of a duct system formed of profile sheets or by means of separate piping from a sufficiently air-permeable granular layer, such as a gravel or light gravel layer. However, such a ventilation layer made of so-15 gravel or light gravel is poor in terms of thermal insulation and does not properly prevent capillary water rise. Also, making an underground floor in this way is quite laborious.

The object of the present invention is to provide a new underground floor structure which avoids the above-mentioned drawbacks in a simple manner and at the same time achieves more efficient radon gas ventilation. This object is achieved by a floor structure according to the invention, which is characterized in that the ventilation layer 25 is a plate-like air-permeable foam layer.

The invention is based on the idea of realizing the ventilation of radon gas by means of a prefabricated floor layer which at the same time acts as a thermal insulation layer and a capillary water rise cut-off layer. The highly permeable foam layer also acts as a pressure equalization layer, to which a vacuum or overpressure can be easily applied to promote radon gas venting. In the construction industry, foam has previously been used solely as thermal insulation, and the foam has then been air-impermeable.

2 75384

When using the sheet-like foam according to the invention, it is easy and simple to make a ventilation layer, and the floor structure can be made in the same way as a conventional underfloor floor. The ventilation layer is load-bearing and no separate ventilation addition means, for example drainage pipes, are required.

Preferably, the ventilation layer is cellular polystyrene, which is used, for example, in drainage sheets.

The invention will now be described in more detail with reference to the accompanying drawings, in which Figure 1 shows a vertical section of a building with a floor structure according to the invention, Figure 2 shows a plan section A-A of the building shown in Figure 1, and Figure 3 shows an axonometric section of the floor structure of Figures 1 and 2.

The floor structure according to the invention shown in the figures has a ventilation layer 1 as the lowest layer of the structure against the ground surface, which is made of a plate-like air-permeable and heat-insulating foam, for example cellular polystyrene. The thickness of the layer 1 can be, for example, 100 mm. The ventilation layer 1 is specially intended for ventilating radon gas from under the floor to the outside air surrounding the building, but the ventilation layer also acts as a thermal insulation and pressure equalization layer as well as a capillary water rise cut-off layer. The ventilation layer 1 is connected to the outside air surrounding the building, preferably by ventilation pipes 5 and 6, which extend to the roof of the building and through the plinth to the wall of the building. The number and location of the ventilation ducts can be varied as required, for example in some buildings one ventilation duct 6 on the roof of the building may be sufficient. Ventilation can be assisted by mechanical ventilation. The permeability of the ventilation layer 1 to 35 is so high that the vacuum equalizes in the area of the building.

Only the actual thermal insulation material of the floor has been laid on top of the ventilation layer 1, in this case in two layers 2 and 3. A concrete layer 4, which becomes the uppermost layer of the structure, is cast on the thermal insulation layers 2 and 35, which can be cast by conventional methods. Concreting should also be completely uniform in terms of joints to the plinth.

In the present example case, in order to increase the load-bearing capacity, rigid insulating television blocks 7 are placed in the ventilation layer 1 to increase the load-bearing capacity of the porous ventilation layer 1. It is not necessary to use rigid accessories if the load from the floor is so small that the own load-bearing capacity of the ventilation layer 1 is sufficient.

Claims (3)

4 75384 An underground floor structure comprising - a porous ventilation layer (1) against the ground surface, specially designed for ventilating radon gas and connected to the outside air surrounding the building, - at least one thermal insulation layer (1) placed on top of the ventilation layer (1). 2, 3), and a concrete layer (4) cast on top of the thermal insulation layer (s) (2, 3), characterized in that the ventilation layer (1) is a plate-like air-permeable foam layer. Floor structure according to Claim 1, characterized in that the ventilation layer (1) is made of cellular polystyrene. Floor structure according to Claim 1 or 2, characterized in that the ventilation layer (1) is connected to the outside air surrounding the building by at least one ventilation pipe (5, 6) extending to the roof of the building and / or through the plinth to the building wall.