During recent years the use of Vacuum Insulation Panels in buildings applications has been improved, because of their both higher performances and lower thickness compared to traditional insulation materials. These performances are due to the interior vacuum degree, which represent also the main problem connected with the applications of this technological solution in buildings constructions: to maintain the vacuum condition the panels are enclosed in an envelope layer, characterized by an higher thermal conductivity. Moreover they have to be assembled to each other or to additional different joint materials in practical building application, generating a thermal bridging effect. The aim of present work is to analyse the critical aspects related to this insulation technology for building application. An experimental campaign through heat flow meter apparatus was carried out with the purpose of assessing the decrease of performance due to the thermal bridges effects considering different joint materials in VIPs assemblies.