Thermal Behaviour of Concrete Walls Around all Cardinal Orientations and Optimal Thickness of Insulation from an Economic Point of View

In this study, it is examined how the thermal insulation and other parameters, such as the orientation of external surfaces and the outdoor/indoor environmental conditions, affect the energy performance of building walls. The analysed assemblies correspond to externally insulated concrete walls, at all cardinal orientations. Their thermal performance is assessed in terms of annual heat flows to maintain the system in balance, while the dynamic thermal inertia parameters (decrement factor and time lag) are also determined. For the aims of this study a one-dimensional lumped model has been adopted by using the finite element method. The analysis also assesses the optimal thickness of the thermal insulating layer from an economic point of view, during the expected lifespan of building structures. Evidently, the varying insulation thickness and orientation of wall configurations, affect the initial cost of the structure installation and the operation cost of the energy consumption (natural gas and electricity).