Karlsruhe Durlach, Germany
The building forms part of a cluster of five large renovated multi-family
buildings from the 1960s within the Karlsruhe district Durlach, where an
integrated energy system is demonstrated within the research project “Smart
district Durlach”. The demonstrated heat pump technology features finned PVT
collectors as single source for the heat pump system. Ultrafiltration are units are
integrated in the drinking water circuit to allow low temperatures and maintain
the hygienic requirements. 13 out of 150 radiators were exchanged to allow a
heating temperature reduction to 55/45 °C. The building was originally built in
1963 and renovated in 1995. The building features a heated floor area of 2112
m² on 5 floors with a total of 30 apartments. The building was renovated
exchanging the windows with insulating glazing (Uwin = 1.7 W/m²K), and adding
layers of thermal insulation (styrofoam, d = 60 mm, l = 0.035 W/mK) to the
façade, cellar and to ceiling, thus reducing the overall U-value of the opaque
envelope from Uenvelope = 1.71 W/m²K to 0.323 W/m²K.