Thermal simulation of building performance with different loadbearing materials

In recent years, overheating of buildings during the summer has become a serious problem. This is the result of a significant increase in the number of cooling degree days over the last thirty years in Europe. As a consequence, increasing energy is consumed by buildings to keep the temperature at a relatively low level in the summer. This prompted us to examine the thermal simulation performance of a typical 50m2 flat with different loadbearing materials used for the external walls. Calculations were made for lightweight cement composites aerated with air-entraining admixture or with the addition of aerogel particles. The results were compared with those obtained for walls based on conventional materials. Simulations were carried out using the Wufi Plus software. The components had a variable width of thermal insulation so that thermal transmittance of all the tested walls was constant. This assumption made it possible to evaluate parameters related to the thermal accumulation of the tested walls. These results demonstrate that the use of lightweight cement-based materials not only improves the thermal insulation of the whole building, but also significantly increases thermal mass of the walls. As a consequence, these type of wall component improve the microclimate, i.e. by lowering the internal temperature of buildings during the summer.