The multi-family house (12 units), dating from 1920 and reconstructed in 1950 will be low energy retrofitted and renovated. The roof will be raised and 5 new appartments on two levels in th attic will be built. To reduce the impact of the construction works on the inhabitants, the addition will be made of pre-fabricated wooden x-lam elements in order to reduce construction time and the interventions on the existing structure.

To enhance the quality of living windowsa will be renewed, the outer walls isolated, a new central heating system with solar panels and a ventilation system installed. The existing appartments will get balconies and an elevator will be added.

Due to this measures the building will reach the low-energy standard: kfw-effizienzhaus 85.