Construction & Technology
Climate protection project “ChristophorusHouse” multifunctional company and administration building with a logistics and culture centre in a sustainable wooden construction with passive house standards
After an intense planning period by the architects Albert P. Böhm and Helmut Frohnwieser, and after only 10 months of construction time, the ChristophorusHouse – a multifunctional building – was opened in Stadl-Paura, Upper Austria, on the 18th of October 2003.
The construction of the ChristophorusHouse includes a lot of the know-how that the builder-owner BBM (Procurement Agency of MIVA), a service provider for development cooperation, had gained in the field of ecology and energy management in the countries of the South. New technologies for a considerate resource management were already applied in the refurbishment of several hospitals in Africa. So it was also one of the aims of the construction of the Christophorus-House to give a credible sign of environmental protection in the North.
Under the direction of BBM, experts from most different fields worked together. Main items of the planning, respectively of the implementation, were the reduction of the energy consumption and the use of ecologically sustainable components. The power engineering team (AEE-Intec, Gleisdorf) was involved in this project and in the whole planning process. By modelling and simulation in the dynamic surrounding of TRNSYS, it could decisively influence the architecture, building method and construction.
After a persistent optimization work, the implementation was started in January 2003. The house was finished on the 18th of October 2003. The “ChristophorusHouse” – project excels mainly in the following innovative areas:
Innovative wood construction
The ChristophorusHouse is the first three-story office building in passive house standard in Austria. Furthermore, it is the first wooden rotunda. 51 solid wood poles and newly developed high-strength wood pole carriers and the remaining glued laminated girders support the approx. 1000 tons weighing building. The building with a useful area of 2.096,07 m², consists of about 90 pre-fabricated elements. Approxi-mately 175m³ of solid wood and glued laminated wood plus more than 7.000 m² of slabs from derived timber products were used. The assembly time took 9 days. 754 m³ of hemp, about 154 m³ of cellulose and approx. 500 m³ of rock wool (for reasons of fire prevention) were used as insulating material. In addition, 33,12 m² of solar front were installed.
Passive house windows
Completely newly developed ecological solid-wood passive house window
Frame: Uf = 0,77 W /m²K
Glass: Ug = 0,6 W / m²K
Heating and cooling are provided by 8 x 100 m Duplex closed cycle earth probes.
In the heating operation, they serve as source of heat for a heat pump (43kW at a
COP of 4,03). In summer, the same system is used as heat sink without employment
of energy, “direct-cooling”. The distribution within the house is carried out by 560 m²
of heating and cooling ceiling ducts respectively floor elements.
In order to provide an electricity supply for the heat pump etc., that is largely CO² –
neutral in the yearly average, a mains-coupled 9,8 kWp – photovoltaic plant was
The air exchange is provided by two separately controlled ventilation systems with
heat recovery through a rotational heat exchanger.
Degree of heat recovery: 78% respectively 86%.
Through a sustainable concept, essential savings could be achieved in the drinking water consumption. All the grey water and rain water is clarified by two biological sand bed filter systems (constructed wetland systems) and fed to the service water cycle for the toilet flush, car wash and plant watering. In addition, low-flush toilets and waterless urinals are used. For the hot-water supply, a 6 m² sized solar system with a solar coverage of approx. 70% was installed.
Day light guidance and energy saving measures
Through an optimized day light guidance towards the inside of the house (atrium), continuous light lines on each floor and the employment of energy saving lamps and appliances, essential energy saving measures could be achieved. The lighting in the offices is adjusted depending on the day light.
At it’s opening, the building already received the certificate as quality-proofed passive house by the Passivhaus Dienstleistung G.m.b.H. Darmstadt. According to the certificate, the heat consumption comes to 14 kWh per m² of surface and year. The blower-door-measuring of the fabric construction at a pressure difference of 50 Pascal showed a value of 0,4 per hour during the building phase. The total annual primary energy consumption for heating, hot-water supply, ventilation, auxiliary current and regenerative cooling comes to 49 kWh per m² of useful area.