Vacuum Insulation Panels: thermal bridging effects and energy performance in real building applications

Due to their very low thermal conductivity, Vacuum Insulation Panels (VIPs) have recently seen a fast development and an increasing penetration in building thermal insulation market. However, there is still a lack of knowledge about their performance when actually applied in buildings. In fact, the thermal bridging effects that occur in VIP junctions are not easily evaluable while produce a reduction of the global thermal performance. In this paper, the linear thermal transmittances related to VIP junctions considering different joint materials between VIPs panels and different wall configurations were assessed through a 2D numerical analysis. Finally, through a quasi-steady state simulation, a parametric building case study was analysed, with the aim to evaluate the influence of the thermal bridging effects on the overall building energy need. The results shows that the thermal bridging effect due to VIPs assemblies have not a negligible influence on the overall building energy performance. (C) 2015 The Authors. Published by Elsevier Ltd.