What are the levels of BIM


As digital twins, the digital specialist models are intended to represent the future building in a realistic, virtual manner. To create these digital twins, specialized software systems are required that have functions that go far beyond the functional scope of conventional CAD systems. This software is, coming from the English, as BIM authoring software designated. The aim is to support a way of working that makes it possible to model the digital technical models in the way that will be built later. The underlying data structures, the schemas, contain classes that allow objects in the real world to be mapped virtually (see information model).


State-of-the-art BIM authoring software usually contains classes for the following object types:

  • Objects for mapping the topological building structure:
    Building, level, room, partial areas.
    These are purely virtual model elements: A building only exists if there is at least one level. A level requires at least one room. A room can only be defined if its room-delimiting components have been modeled

  • Objects for mapping the topological building structure:
    Walls, columns, ceilings, roofs, stairs, openings
    These objects indicate that they are usually made on the construction site from building materials, are usually aligned along a line and have a layered structure. Wall and ceiling cladding are defined as the outermost inner layer of these components, roof and facade cladding (if there is no curtain wall) as the outermost outer layer.

  • Objects for mapping routes:
    Cable routes, pipelines, ventilation ducts.
    These components are arranged in a line and usually penetrate several space-delimiting components.

  • Objects for mapping built-in parts and inventory:
    Doors, windows, roller blinds, sanitary objects, switches, sockets, pipe and ventilation fittings and accessories, lighting, other building services components, furniture and equipment.
    These objects are usually transported to the construction site and installed. They can be exchanged without interfering with the statics of the building. These objects can consist of several components or they can themselves be a component of another object. Example: The door leaf, frame and handle each exist as individual objects and together form a door object.

  • Objects for mapping systems:
    Curtain walls, supply air, exhaust air, drinking water supply, sewage disposal, heating, electrical power supply.
    These systems are purely virtual and require at least one component that is assigned to them. Most supply engineering systems can be modeled with a combination of routes and fixtures. In general, an attempt is made to assign a component to each system-relevant function.

Expertise on the subject


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What is an information model?

The digitization of information for the description of objects, systems and processes takes place in a structured, specific form.