Evaluation of long-term performance of VIPs

Apart from the higher initial cost for using vacuum insulation panels (VIPs) in buildings there is still hesitation among architects and engineers whether these materials will withstand long-term use in buildings with a service life of 80-100 years. To evaluate the long-term performance, further investigations are needed. VIPs have been used in buildings since the 1990s and there already exists experience from using them in various applications. This paper presents the experiences from two field studies of a previously non-insulated wall with VIPs and a district heating pipe with hybrid VIP/PUR insulation. Measurements of the relative humidity in the wall showed that there is low risk of condensation in the VIP layer. Temperature measurements in the wall during the period 2010 to 2015 show no signs of deterioration of the VIPs. The same conclusion was made based on the temperature profiles in the district heating pipes during the period 2012 to 2015. The measurements are on-going to determine the long-term performance of the VIPs in different applications. (C) 2015 The Authors. Published by Elsevier Ltd.