The demonstration site #3 consist of a three story apartment block with 58 apartments located in the city of Frederikshavn, in the area Munkeparken. The demonstrator building has a built area of 4235  m². The building is part of a complex comprising in total 4 buildings and belongs to the social housing company Frederikshavn Boligforening (FB). The retrofit intervention will include replacement of windows with smart windows, VIP insulation around smart windows, and installation of Nature Based Cabinets for IEQ.  The rehabilitation plan has been scheduled for summer 2020.

The building was constructed in the 1960’s using massive brick for external and internal walls, concrete slabs and wooden roof construction. The facade cavity has previously undergone refurbishment where air cavity has been filled in with mineral wool granulate.

FB approved in 2012 a long-term energy policy, where the goal was to establish “zero-energy apartments” or as minimum apartments that fulfill Danish NZEB requirements of maximum energy use of 20 kWh/m² year of primary energy. At present several apartment blocks both new and renovated fulfill this goal. FB has developed their own building energy monitoring system to be able to monitor energy use and IEQ in individual apartments as well as local renewable energy production, which is implemented in all new constructions and renovations.