For the purpose of energy conservation, modern buildings are becoming more and more air-tight and generally rely on a mechanical ventilation system for the supply of breath air in the rooms. According to literature, solar air heating systems can contribute in a cost-effective way to the heating and ventilation of utility buildings. Especially cost-efficient, unglazed, façade integrated solar air collectors seem to be an attractive new market for façade renovation. To demonstrate the technical feasibility of generating heating energy on facades, a demonstration plant based on an unglazed solar air collector was installed in 2013 in the south façade of a demonstration building and was intensively studied using energy metering during a three month period in winter. The investigation focused on heat distribution in the collector, energy efficiency and achievable net energy yield. First, air tightness of the collector was investigated by means of infrared pictures. No major air leaks at the collector edge or along the collector surface were observed. Then, an energy monitoring was performed over a test period of 3 months. The paper describes the measurement results and discusses the energy performance issue in the shape of a benchmark analysis with a building integrated PV system.