What is BIM?
Building Information Modeling (abbreviated: BIM) describes an innovative working method in the construction industry which can be used for optimizing the planning, construction and maintenance of buildings, through the use of digital modelling.
The following BIM definition from the US National BIM Standard Project Committee has been accepted by a variety of professionals and organizations around the world:
“Building Information Modeling (BIM) is a digital representation of physical and functional characteristics of a facility. A BIM is a shared knowledge resource for information about a facility forming a reliable basis for decisions during its lifecycle; defined as existing from earliest conception to demolition. (NBIMS-US, 2016) “
The basis of BIM is a digital, object-oriented 3D computer model, which means that the individual components are depicted as objects that have geometric dimensions. This is a crucial difference compared to the conventional CAD model, where the three dimensions can also be mapped, but the drawings are made up of graphical 2D elements such as lines and texts. As for the BIM, further features can be assigned to the virtual models of real elements (ceilings, roofs, windows, walls, etc.) such as material, manufacturer, cost, etc. The dimensions can also be expanded, 3D refers to the geometry (x, y, z), and the following factors can be integrated: time schedule (4D BIM), costs (5D BIM), lifecycle facility management (6D BIM). This can be used as a database where all building-related information is stored. Ideally, this information is accessible to all stakeholders throughout the project. This means that planning, construction and future operations use the same data model.
The CAD software imitates the traditional “paper & pen” working process, and in case of changes the new data must be updated manually on each drawing. The quantitative determination must also be manually adjusted, and the project participants must be informed about the updated status, which they always reconcile with their disciplines. This requires a huge coordination effort, which can be significantly reduced with the BIM model. At BIM, the building is built on the computer before construction – “build digitally first”. The respective changes are made to the central project file and both the drawings and the database are automatically synchronized and are immediately accessible to all parties involved. Every planning step becomes comprehensible and transparent with this logic.
Benefits of BIM
Visualization
Buildings or each of their elements can be visualized, which is useful both during planning and construction
Higher planning quality
Better data quality through a shared database which is constantly synchronized
Clash detection
Clashes between individual disciplines get corrected before construction begins
Increased efficiency
The improved data synchronization increases the productivity of the planning process in terms of quality, costs and deadlines
Collaboration
Coordination is much easier due to the improved information exchange between planning stakeholders
Documentation
Continuous and immediate availability of data as the database is continuously built during the entire project