A multi-LOD model representing fuzziness and uncertainty of building information models in different design stages

The design of a building is a complex process in which a solution is developed iteratively in a way that fulfills the objectives and boundary conditions of multiple designs and engineering disciplines. The planning process in the Building Information Modeling (BIM) approach starts from a coarse model and gradually refines it via multiple steps, described as levels of development (LOD). So far, there is no method to explicitly define an LOD’s requirements nor any specification of its uncertainty. At the early design stages, where only rough information is available, a BIM model appears precise and certain. This can lead to false assumptions and model evaluations, for example, in the case of energy efficiency calculations or structural analysis. Hence, this paper presents a multi-LOD meta-model to explicitly describe each individual LOD’s requirements, which makes it possible to check the consistency of the geometric as well as the topologic and semantic coherence across the different LODs.