BUILDING CLASSIFICATION FOR BIM – RECONSIDERING THE FRAMEWORK

The purpose of building classification systems is to provide the sector with agreed and standardised terminology and semantics, e.g. in systems for technical specification, cost calculation, and exchange of information. There is a growing need to use classification systems in a BIM context. In international construction projects and international construction product trade there is a need both to translate between national classification systems and to develop common systems. The idea behind the international framework standard for building classification ISO 12006-2 is that national systems would be easier to compare if they adhere to the class definitions suggested in the standard. A study of two classification systems, the BSAB system in Sweden and the DBK system in Denmark, both within the framework and yet not compatible, has risen the idea of a deeper analysis of the theoretical basis for the ISO 12006-2 classification system to find a solution to this problem. The project has developed such a theoretical framework in order to clarify the relationship between classes representing parts of buildings in the ISO 12006-2 standard, specifically the Construction entity part, Element and Work result classes. This is specifically needed when the standard is used in the context of BIM, since building models include both specialization and compositional relations among information objects representing parts of buildings. The proposed theoretical framework is based on a systems view on the built environment that distinguishes constructions in four main compositional levels: construction entities, technical systems, building elements and components. Based on the theoretical framework developed in this project, possible new interpretations of the classification standard ISO 12006-2 are discussed.