Responsive Building Elements (RBEs) are technologies for the exploiting at the building scale renewable energy sources and the opportunities offered by the environment. Among the RBE concepts identified by the IEA-ECBCS Annex 44, Advanced Integrated Façades (AIFs) is probably one of the most promising technologies. Important players in the field of the façade have started to develop integrated modular façade systems (Multifunctional Façade Modules - MFMs), with a dynamic behaviour and interacting with the other building services, in order to reduce the building energy consumption and maximize the indoor comfort conditions. In the frame of a research activity aimed at the development of solar and active building skin, a MFM has been conceived and a prototype realized for experimental evaluation. The work presented in this paper illustrates the first results of the experimental campaign on the RBE-MFM called ACTRESS (ACTive, RESponsive and Solar). The ACTRESS façade module is being tested by means of a Test Cell apparatus. The main physical quantities (e.g. heat fluxes, temperatures, transmitted irradiances, PV power, air flows, etc.) are continuously measured by means of more than 70 sensors placed on the mock-up. A detailed picture of the monitoring system is given with the description of the measurement procedures. Preliminary results concerning the behaviour of the system during summer and mid season are illustrated and discussed.