Full renovation and new, clean heating
The aim of this project was to protect the climate, increase security of supply and strengthen regional value creation at the same time.
When you’re looking for a new flat to rent, the heating costs matter. In Germany’s western Sauerland region, non-profit housing association Hemer eG knew this, and made sustainable and affordable heating a priority when renovating a residential building in Hemer.
It decided to put in nine decentralised ventilation heat pumps, one per apartment – covering 616 m² of living space – to be used both for ventilation and for hot water from recovered waste heat. A modern air-to-water heat pump provided central underfloor heating. These replaced the old water heater and gas condensing technology.
Key Facts
| Buildings | Heat Pump and Source | ||
| Location | Hemer, Germany | Number of HPs | 9+1 |
| Construction | 1952 | recovered waste | recovered waste heat + air |
| Project type | retrofit | Type of system | individual |
| Heated distribution | underfloor | Capacity | 40kW |
| Heated space | 616 m² total | Model | Dimplex LA 40TU |
| No. of aparments | 9 | ||
| Insulations | retrofitted | ||
| Space and Domestic hot water heating | |||
| Heating temperature | 35°C | ||
| Heat output via | underfloor heating |
Description of the technical concept
The advantages of the compact hot water ventilation system made it easy for the installer: no new hot water pipes had to be laid through the entire building; instead, preparation and extraction are each located within one flat. This also greatly reduces energy losses. The short distances also made it unnecessary to install circulation pipes.
“The house was built in 1952 and was half empty, That’s why we carried out a full refurbishment and rebuilt the staircases.” – Peter Meyer, spokesman for the Board of Directors of Hemer eG.
“The flats, which range in size from 50 to 110 m², have been fully rented again since the first ‘groundbreaking’ of the project. In addition, the tenants feel very comfortable in their new home, also due to the good indoor climate,” – Peter Meyer
Case study delivered by: European Heat Pump Association