S-HOUSE Passive house made of straw

Further to my post about Swedish passive houses, here is a very interesting project about passive houses using renewable resources.

Sustainable construction can be defined as follows: Not only the building concepts but also the components and materials which are used have to meet the present needs of the users without burdening future generations with waste disposal problems or prolonged use of an out-dated building design. Thus sustainable architecture means: form follows ethics, i.e. the design is the result of a careful consideration of functions, materials and their life-cycle performance including long term perspectives, present and future human needs and social aspects. This is the basic principle under which the S-HOUSE, a passive solar house made of renewable resources, is constructed.

Passive solar house technology is already well known. Building materials based on renewable resources are present in some areas (e.g. wood). But the combination of both is quite unique. This combination is made visible by the S-HOUSE, an office and demonstration building at the Center for Appropriate Technology in Böheimkirchen / Austria. After a careful planing phase the building was put up in early 2005.

The challenge of the S-HOUSE-project consists in combining the high energy standard of passive solar house technology (less than 15 kWh/m²a) with the use of renewable resources and herewith to benefit from the advantages of both.

According to results obtained from the fundamental studies, the facade was built as a structure made of wooden boards and straw balls that are pressed and mounted free of thermal bridging. This straw proofing was provided with a layer of clay plaster and a wooden casing. Wind-proofing is ensured by the wooden board construction. The south facade is fully glazed. Towards realisation of a passive house compatible building mantle, the necessary straw ball proofed floor and ceiling elements were also developed. Thus, the entire building is “packaged” with straw and it provides optimum heat insulation.

The building stands on a sub-ventilated building slab, which is supported by individual footings. This facilitated a significant reduction in the use of mineral resources as compared to a conventional foundation; this construction also does not allow accumulation of cold and humid air in the floor slab area. This optimises the degree of insulation in the floor construction. The roof has been designed as a membranous roof, which is made of a “flying” wooden construction mounted over the straw insulated wooden ceiling and covered with a rubber membrane and greened.

The S-HOUSE acts as an office and exhibition building and as a turntable for dissemination of information on sustainable building methods. For the project, spreading the know-how and experience acquires much importance. Even during the set-up phase, the results of the planning processes were discussed thoroughly at international forums as well.

The project was presented at the EXPO 2005 in Japan where it received the “Global 100 Eco-Tech Award” as one of the best projects worldwide in the field of resources efficiency and safeguarding the climate.