Grünes Zentrum, Holzkirchen | Germany

Photos: © Müller-Naumann, Müllerblaustein

The new building for the Office for Nutrition, Agriculture and Forestry was built with a view to extended use. This building complex includes an agricultural college with a cafeteria, a residential school and an administrative building for advisory services. It was designed as a certified passive house with a timber construction. Entering through an entrance courtyard, visitors come to a central foyer to which all the separate areas are directly connected. The cafeteria and recreational rooms are housed in the central building with direct access to the garden courtyard. The residential school is separate from the main complex.

Project Office for Nutrition, Agriculture and Forestry

Place Holzkirchen, Germany

Year of construction 2015

Contracting authority Free State of Bavaria

Client Bayerischer Bauernverband BBV

Architecture Project planners Gerhard Simson and Wilfried Dederer

Execution müllerblaustein GmbH

Grünes Zentrum, Holzkirchen | Germany

Photos: © Müller-Naumann, Müllerblaustein

The „Grünes Zentrum” in Holzkirchen is located on a green belt within the community, which separates a residential area from a business park. A meadow with scattered fruit trees was planted on the southern piece of land to even out the levels and for recreational purpo-ses. The two wings of the building form a public entran-ce courtyard and a garden courtyard. The differences in level were evened out by a terraced college garden.

The buildings have a usable floor area of 5,000 m² with a heating requirement of less than 15 kWh/m²a and a total primary energy requirement of only 102 kWh/m²a. The construction costs were € 10 million.

The building was constructed as a modular prefabricated timber construction on a reinforced steel slab on foam glass gravel. The exterior shell has a timber post construction with blow-in insulation and back-ventilated timber façade. All load-bearing elements, such as interior walls, including ceilings, staircases, lift shafts and firewalls, were produced with binderholz CLT BBS elements. The roof construction was executed with rafters and a clay tile cover.

There are no thermal bridges in the entire construction, which is permeable. All rooms have large-scale visible wooden sur-faces and drywall plaster walls. This has a positive effect on the indoor climate and enables the interior humidity to be naturally regulated. The thick, relatively heavyweight timber insulation regulates the ingress of heat in summer. Outstanding acoustic insulation is provided together with the triple glazing.

The residual heat requirement is provided by heat pumps with geothermal probes and underfloor heating. The system can be used in summer for extremely energy-efficient passive cooling. A photovoltaic system was designed but has not yet been installed.

All the rooms are naturally lit and have external slatted blinds to provide sun shading and to control the lighting. The lamps provide both direct and indirect lighting. The reflection of the light on the timber ceilings creates a pleasant and natural lighting ambience. The construction materials essentially exude their natural colour and finish. The exterior façade was constructed using pre-greyed larch wood profiles.