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6th Austrian workshop

"Industrial Prefabrication: Buildings Mass-Produced or Made to Measure?"
Key results

Industrialization - A way out of the crisis?

Industrial prefabrication is expected to reduce costs through faster construction, to increase construction quality, to eliminate dependence on weather conditions at the construction site, and to improve coordination of planning and construction. These four expectations were named by other attempts in the past as well. What is missing is the most essential point, namely the overall picture. At issue is the connection between ecology, urban planning, and architecture.

Best-Practice Developments

• The Austrian housing association BUWOG constructed a housing development in Vienna/Leberberg (A-1010 Vienna, Ernst-Heiss-Gasse 3) using prefabricated concrete components based on a modular building system of the Austrian architect Heinz Ekhart. The building was constructed with aerated concrete beams and reinforced concrete floor slabs. Basically, everything is prefabricated and needs only be assembled at the construction site. The buildings are constructed as the sum of identical elements. Interior and exterior space flow into one another, there is no façade to separate them. Filled an open elements alternate with one another. An interplay of light and shadow emerges. The system's three-dimensionality permits any shaping of space or height.
• The Austrian company Kohlbacher developed a residential timber frame construction system (HSK) especially for multi-story residential building. The HSK system consists, simply put, of basic systematic elements that architects and builders can employ according to their varying needs. The elements in question include internal walls, exterior walls, partition walls, hung ceilings, and countless other adjoining details. The walls are made with solid wood elements. This is a combination of skeleton and belowground construction which has the advantages of both. The high degree of prefabrication inherent in skeleton construction is utilized and at the same time there are 6 cm of solid wood sheeting with Heraklith that serve as a storage mass and as sound insulation. All the timber used is glued laminated timber and needs no wood preservatives. Over 400 residential units in Austria have been built using the Kohlbacher HSK system.

More prefabrication - more planning

The degree of industrial prefabrication must be increased in order for prizes to be competitive. A higher degree of prefabrication, however, requires more work on the part of planners, which means that more time must be invested in planning processes. There is a necessity of making precise commitments in certain instances in the planning process. Optimization should be aimed for so as to transcend the trades boundaries.
Prefabrication means investing in preparation, so that things proceed smoothly. Planning and organization must be intensified, interaction issues for an optimization and cooperation in a multi-trades context has to be defined.

Deficits in cooperation between planning and construction

There are deficits in cooperation between planning and construction affecting adversely the development of prefabricated systems. For this reason, more transparent forms of planning cooperation must be worked toward, and new forms of communication and/or exchange between planners and builders must be defined. One suggestion is to involve contractors to a much greater extent in planning building details.

High quality at low cost

One of the most important arguments for prefabrication in building construction, one which cannot be brushed aside, is that prefabricated products can broadly deliver high standards of quality. This aspect should be emphasized in the setting of goals and in argumentation for prefabrication.
Thus through prefabrication improved resource efficiency can become standard as well: through energie-efficient building systems, production with ecological raw materials and material-efficient production processes. One argument against it is that additional transport may become necessary, because prefabrication means also that certain production processes take place on a European or global level.

Maintaining individuality

Prefabrication must come to be seen as separate from the concept of mass production. In future, industrial prefabrication must face the challenges of accepting individuality as a quality indicator and taking account of users' needs and wishes. We cannot build at the cost of the individuality of future residents by inflexible modular building systems. The interchangeability of components, for example, in systems that can later be modernized, allows for flexibility of use.

High levels of flexibility with prefabricated building components

The workshop experts see the future of prefabrication in the reasonable use of prefabricated building components. This application of prefabrication harmonizes with sustainable flexibility and allows for individuality despite standardized industrial production. Complete prefabricated systems reach their limits in comparison to prefabricated components when they are not further developed. They can maintain their position only if they change along with new developments in the field.

Prefabrication in renovation

Prefabrication is not being taken advantage of in renovation efforts at all. Instead, work is being done to repair existing building deficits, above all in thermal insulation. Comprehensive renovation concepts are lacking. As a first step, it is necessary to do research into the question of which buildings could benefit from a prefabricated renovation system such as a complete façade including windows, integrated noise prevention and insulation, thermal protection, shutters, etc. Moreover current rent law, apartment ownership law and laws to protect historical buildings hinder the development of prefabrication for renovation.

Changes in the business environment are to be expected

The development of integrated production management in the building sector - of which development prefabrication is a part - is expected to lead to radical changes for businesses due to cluster formation. Local firms will cease to exist as they do today and consortia will take over the more favorable position.

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