Text description provided by the architects. The 80m² small row house had only been selectively maintained since its construction in 1949. In order to ensure the processes in the house as well as the energetic refurbishment, we designed the current conversion accordingly holistically. The basement had to be structurally strengthened in order to open up the ground floor into a kitchen-living room. The bathroom on the upper floor was enlarged. We opened up a room chamber of 9m² to a family room with an office. In a second stage, the building was extended by a whole storey with wooden elements. The attic can now be used as a living room and retreat with another bathroom. After completion, the building now offers 120m2 of living space with a 40m2 basement.
We supplemented the façade with 20 cm thick wood fibre insulation; the simple wooden windows were replaced with triple-glazed wooden-metal windows. Inside, we worked with high-quality, durable and exclusively natural materials, added to the existing and preserved the old wherever possible. Broken and damaged areas were simply painted, filled with cement or left as they were. The resulting scars and traces meet the new requirements without denying the substance found. The almost 35m2 planned integrated PV system was discarded after ample deliberation and profitability calculations. The solar power is now obtained from a cooperative in Zurich.
The row house is located on a road with no traffic, which meant that all the elements had to be lifted over 45m to the site using a jib crane. This meant that the addition of the storey was carried out in a generous geometry within one day. The logistics also required precise planning in order to keep the number of approaches and corrections to a minimum. The energetic renovation by replacing the windows, the wood fibre insulation and the roof, allows that in winter only two heating radiators have to be used, both of them were reused from the existing building. On hot summer days, the cool interior temperature is maintained by the existing masonry and the newly applied natural coating of wood fibre insulation. Night cooling can be actively supported by the two skylights. The refurbishment was nominated for "The Best Refurbishment 2020".