Thermal Behavior of Old and Recent Façades

Abstract

Losing heat additionally results in greater energy expenses and waste of resources. In any construction building, the façades ensure the heat transfer between the exterior and the interior surfaces of the structure. The thermal transfer of a façade is dominated by conduction. This exchange makes them responsible for guaranteeing thermal comfort to the occupants. Uninsulated outside walls can cause substantial heat loss, particularly during the winter. The heat is able to pass via such façade, leaving it hard to keep the appropriate temperature inside the construction. Furthermore, there is traditional outside insulation that uses isolative boards, which come in a variety of materials. They require a coat of render on top to provide additional protection from the outdoors as well as a beautiful finish. Impermeability and additional costs are the main disadvantages of such systems. In recent façades (rainscreens), the use of ventilated or unventilated cavities influences the thermal resistance. The rainscreen tends to have lower thermal transmittance than the stone façade. The thermal transmittance of the curtain wall depends on the thermal transmittance of the glazing and that of the mullions/transoms including the spacer of the double-glazing, calculated from a 2D analysis, so the total thermal transmittance will be a weighted average value. Surface or interstitial condensation occurs when humid air touches a surface T less than the dew point temperature; it is less likely to occur in a recent façade than in an old one. The aim of this topic is to achieve an energy comparison between two identical resident structures. The first one was provided with an old façade; however, the other house had a recent façade. The obtained results show an important saving of energy of the recent façade (refund in electricity bills), ensures thermal comfort, reduces embodied carbon, and protects the planet, the atmosphere, and the environment.