In addition to the insulation values and their impact on energy consumed, we must also take into account comfort and well being within the building. Once again, Hebel stands out in this area due to its excellent thermal qualities. During periods of intense heat or solar radiation, a well insulated building with good thermal inertia will remain pleasantly cool during the day and retain a sufficient temperature at night. Obtaining good thermal comfort requires not only external walls with high thermal capacity (that is, with a high mass to be able to “absorb” the heat), but the wall must also be insulating so that the heat does not pass to the other side too quickly. A simple insulant has too low a mass and so cannot store the heat. With a light roof composed of insulation and steel sheet or tiles, a “caravan” effect will arise. This is a rapid heating of the building subject to solar radiation causing discomfort due to excessive heat. The only solution to combat this heating is air conditioning, which is very costly in terms of energy. Hebel has the characteristics of an insulating material and possesses a high mass (between 400 and 700 kg/m3). Hebel meets the conditions for high thermal inertia. Numerous tests have shown the thermal efficiency of Hebel slabs.
