High Density (20 DV, 24DVor 30DV) Polystyrene Sheets are used for most Ground Slab Insulation projects In South Africa. The density of the sheets is determined by the loading requirement of the project. High density polystyrene has significant comprehensive strength.

The thickness is determined by the Thermal R-Value requirement of the project. In South Africa a minimum R-Value of 1 is required for residential buildings where underfloor heating will be installed. This equates to a 40mm sheet thickness.

Even if underfloor heating isn't going to be installed it a good idea to insulate the ground slab.

Our ground slab insulation sheets are most often bought in 1200mm x 2500mm sheets that are then cut and placed on site where the insulation is required. The concrete reinforced slab is then cast on top of the high density sheets.