A review of the challenges posed by the use of vacuum panels in external insulation finishing systems

Abstract

The worldwide demand for energy efficiency calls for improvements in the thermal performance of buildings. As a result, there is a growing interest in the use of high-performance insulation materials such as vacuum insulation panels (VIPs). Due to their low thermal conductivity, high insulation levels can be achieved with thinner walls than is possible with conventional thermal insulation materials. An interesting solution might be to combine a vacuum insulation panel with the well-known external thermal insulation composite system (ETICS). However, in terms of practical application and long-term performance, this solution needs to be looked into further.This paper aims to review the challenges posed when using VIPs in the external insulation of buildings. First, the main advantages and anomalies of ETICS are identified, after which the available VIPs solutions intended for external insulation are explored. Some case studies are presented and the main conclusions that may be drawn from these are highlighted. The difficulties of incorporating VIP products into ETICS are addressed. These include adapting/introducing covering layers to allow flatness and facilitate the handling of the products, defining and assessing a suitable fixation system, and ensuring the connection between construction elements. The main concerns regarding the ETICS with a VIPs solution are also discussed, such as edge thermal bridging, service life performance and installation, and the economic viability of the solution. Finally, we propose guidelines for performing a good evaluation of ETICS solutions that use VIPs.