Monitoring Results and Optimization of a Facade Integrated Ventilation Concept for Building Retrofit

An office building of the Fraunhofer Institute for Solar Energy systems (Fraunhofer ISE) in Freiburg was retrofitted in 2012 with an innovative concept based on technology integration in the façade. Prefabricated window modules integrating air inlets and outlets, façade integrated air ducts and a heat and moisture recovery ventilation device were implemented. A long term monitoring was set up including energy, temperature, CO2 and humidity measurements. The results of this monitoring and an analysis of the system are presented, focussing on the influence of façade integrated air ducts on the energy performance of the whole system and on the thermal comfort. A specific definition of the global energy efficiency of façade integrated ventilation systems is proposed and used to evaluate the performance of the system. On the basis of the monitoring results, a simulation model could be defined and used to optimize the integration concept by testing different geometries and materials. The last developments of the integration system are presented such as the next step of this work: the implementation of the system on the façade of a multifamily home in Frankfurt.