Sustainable renovation of Witteveen+Bos Leeuwenbrug office

Witteveen+Bos can make an important contribution to sustainable development through our own business operations. In 2017, we therefore embarked on the renovation of the largest Witteveen+Bos office in Deventer, the Netherlands. Over the course of about a year, the Leeuwenbrug (LB) building has been extensively renovated with the aim of creating a pleasant and sustainable working environment for approx. 450 colleagues. There were three reasons for the renovation: the building was outdated in terms of both technology and aesthetics, Witteveen+Bos wanted to introduce its PLUSworking concept in Deventer too, and also wanted to be able to showcase our expertise in the field of improving the sustainability performance of existing buildings to clients and visitors – and to inspire them. ‘The result is a building with an excellent sustainability performance, incorporating various innovative solutions.

The TripleAqua climate system is one of the main sustainable solutions applied in the renovated building. It is a special type of heat pump that can both heat and cool at the same time. The heat produced during cooling is directly added to the warm water circuit, helping to save energy going into the heating process. The system also has several internal buffers that temporarily store surplus heat or cold for later use. Application of the TripleAqua system at this scale is unique in the Netherlands. Besides the installation of a heat pump, other measures have been implemented to make the building more sustainable. The building is no longer connected to mains gas, and it is now fully insulated, including facades, floor and roof. Energy-efficient LED lamps were used for al light sources. The presence of people in the conference rooms is detected based on carbon dioxide emissions: the lights are switched off when no-one is around. We have also installed 326 of solar panels on the roof of the building.

In addition to the above-mentioned measures, many other innovative solutions have been implemented, helping to upgrade the building’s energy label from level D to level A+++. And thanks to all sustainability measures, its total energy consumption has been slashed from 450,000 kWh to 250,000 kWh. Energy consumption per employee has been reduced even more, because with the renovation the number of workstations has been increased from 240 to some 350. A major bonus of this project has been that it allowed Witteveen+Bos employees from many different disciplines to contribute, enabling them to learn a great deal. This knowledge about improving the sustainability performance of existing buildings can now be applied in projects for our clients.