Under Concrete Insulation offers insulation to certain materials, out of which the heat energy radiates. The concrete slab must be insulated to a greater extent. If it not insulated properly, then the slab is likely is loose ten percent of the heat. Concrete slabs form a good example of heat radiation. Therefore to insulate a concrete slab, Under concrete insulations are used. It is based on the principle called Thermal Bridging. This principle states that, heat loss tends to occur when concrete slabs and wooden joints that are not properly insulated come in contact with each other. By forming a thermal break, such a contact could be avoided. This can be achieved by using an insulated material in between two layers, so that the transfer of heat can be stopped. Polysterene is a material, which is used to make Under Concrete insulation and this insulation is primarily meant for the concrete slabs.