The new office block for the installation company Imtech in Eindhoven, opened on October 7th 2011, is an exceptionally sustainable, ultra low-energy building. The design by Bo.2 architects is the first office building in the Netherlands to be certified as 'very good' by the Dutch Green Building Council in accordance with the BREEAM-NL assessment guidelines.
This project is situated in the middle of a residential area on the outskirts of Eindhoven. The two building volumes, offices and industrial building, were therefore designed with the same external features (horizontal strips and sustainable façade panelling) in order to create a less ‘industrial’ appearance than usual.
The concrete base blocks form a conceptual connection between the various parts of the building, and also encompass the inner courtyard and outdoor storage. A park-like space was designed to surround the complex. Here, rain water can on the one hand infiltrate naturally into the ground, and on the other, partly be stored in underground containers. This water is used to flush the toilets.
The sustainable-building measures first and foremost ensure that the exploitation of the building is much less expensive. The investment is paid back more quickly while the building is in use. The favourable relation between façade and floor-surface area, and the favourable orientation of the building towards the sun minimizes the loss of heat in winter and reduces the build-up of heat in summer.
A choice was made in favour of wooden, rather than more maintenance-friendly aluminium window frames. By designing extra structural glass panels in front of the wooden frames, the wood is protected from exposure to the weather, so that it requires much less maintenance. The closed parts of the façade consist of Eternit and Platowood siding panels. Platowood is thermally preserved wood. The ‘boiling’ of the wood ensures that the low environmental impact of the use of (FSC certified) wood is combined with a long lifespan.
Eternit is a recyclable panelling material consisting of wood pulp and cement. Due to the extreme hardness resulting from this combination, it is exceptionally durable. Moreover, these Eternit panels are produced at relatively low temperatures, so that the environmental impact during manufacture is lower than, for example, with aluminium products. The panelling is dismountable and mounted without the use of screws, which makes the façade 100% reusable.
For low-energy generation of heat and cold, the choice fell on thermal storage in aquifers. With this system, heat and cold are stored using the water in course-grained sand layers or porous limestone or sandstone in the ground, the so-called aquifers. In the case of Imtech, there are two water wells on top of each other at different depths down to approximately 80 metres below ground level, separated by an impermeable layer (aquiclude or aquifuge).
The transport of heat and cold to the climate ceilings (integrated heating and cooling in a ceiling system) is effectuated using water. Apart from this, there is also a CO2 controlled ventilation system that is controlled by human presence. When there is no activity in a room, the ventilation is reduced by decreasing the turning speed of the ventilator. This saves energy and diminishes unpleasant noise in the piping.