A Parametric Study of Thermal Performance of an Exterior Wall Insulated with Vacuum Insulation Panels

The requirements regarding thermal insulation of the new buildings and thermal rehabilitation of the existing buildings tend to reach a threshold of insulation which allows to fulfill the necessary requirements for a low-energy building. To achieve this level of thermal insulation involves using either thick layers of conventional insulation (polystyrene, mineral wool, etc.) or high thermal performance materials. Vacuum insulation panels are high performance thermal insulation characterized by very low thermal conductivity, from 5 up to 8 times lower than conventional thermal insulation. Vacuum insulation panels consist of a core (the main component being in generally fumed silica) surrounded by a multilayered film. The assessment of the thermal performance of these elements requires the evaluation of the linear thermal transmittance due to themal bridges which occur at the edge of the panels. The results of a parametric study of the thermal performance of an exterior wall insulated with vacuum insulation panels are presented. The study highlights the parameters with the largest impact on the effective heat transfer coefficient of the wall.