This type of flooring with high mechanical performance is used for industrial buildings or cold storage rooms at low temperatures where resistance to static and dynamic loads is required. It is usually made of cement to allow for the circulation of work vehicles. The thermal insulation recommended for this application must have a high compressive strength, as it must bear extremely heavy loads. Extruded polystyrene is the ideal insulation for this type of application: not only does it have a high compressive strength, but it is also highly resistant to low temperatures. It ensures safe working even at temperatures constantly between -50 ºC and -60 ºC. Not only is it important to assess crushing compressive strength of the selected insulation at 10%, but also long-term compression at 2%. Compressive strength at 2% for plastic materials is the maximum force beyond which the panels are deformed due to the breaking of the cells. The breaking of the cells worsens the thermal and hygrometric properties along with the mechanical characteristics. The other characteristic indicates the maximum force that can be continually applied on the product in the long term (20 years) until a deformation of no more than 2% is obtained. This is the value that needs to be considered when planning and sizing the reinforced footing.
The stated values for X-FOAM® extruded polystyrene are:
Product at 10 % of crushing 2 % of crushing
X-FOAM® HBT 300 120
X-FOAM® HBT 500 500 220
X-FOAM® HBT 700 700 250
Laying: once the floor is cleaned and leveled, the X-FOAM® HBT 500 insulation panels are applied trying to cover the entire surface. Once laid, the insulation panels do not require mechanical fastening. If the structure is part of a cold storage room, before laying the insulation layer, a waterproof membrane is applied as a barrier to vapor. A separating layer is to be applied on the layer of X-FOAM® panels to protect the insulation from the cement that will be cast on the reinforcement grid placed on the separating layer. The purpose of the reinforced concrete of at least 8 cm in thickness is to distribute the loads. A final layer of asphalt completes the structure.