In situ performance assessment of vacuum insulation panels in a flat roof construction

The recently introduced vacuum insulation panel (VIP) is a space saving alternative to conventional thermal insulation, thanks to its five to eight times higher thermal resistivity. As gas permeation through the envelope barrier may drastically reduce the insulation efficiency, aging effects and service life expectation are crucial aspects of those high performance insulation units. In the present paper, monitoring data from a terrace construction over more than 3 years are reported. The results are compared with laboratory aging data at constant conditions by linear and Arrhenius weighting of the dynamic boundary conditions. Based on satisfactory agreement, a similar approach is applied for the prediction of the thermal performance after an installation time of 25 years, the common time used for building design regarding energy performance.