Building Information Modelling (BIM) is a very broad term that describes the process of creating and managing digital information about a built asset such as building, bridge, highway, tunnel, and so on.
A BIM object usually has 3D geometry that describes its physical appearance, as well as data that describes what it is, how it is classified, its performance values, material types, expected lifetime, and so on.
In parametric models, each object need only be defined once and can then be placed in the model in multiple locations as required. If the object is then changed, these changes will appear throughout the model. This makes models automatically consistent and reduces errors.
There are two basic types of object: component and layered.
- A component represents building products that have a distinct geometrical shape, such as furniture, windows, doors, equipment, and so on.
- A layered object is a product that does not have a fixed shape or size, such as flooring, carpets, insulation materials, ceiling materials, and so on.
Objects can also be classed as ‘generic’ and ‘specific’:
- Generic (or library) objects are used during the initial design as ‘placeholders’, expressing the need for a specific object to be selected at a later date.
- Specific (or manufacturer) objects are those that represent products specific to a manufacturer.
Objects may be available in specific formats suitable for Revit, Archicad, and so on, and they can be provided in open exchange formats.
The NBS National BIM library is an online environment created for the storage of manufacturers’ BIM object model files. All BIM objects accessible through the library are authored to NBS standards. This ensures the user is able to select and use BIM objects which contain all the information needed and are compatible across all working platforms.
In 2014, NBS published the NBS BIM object standard. This defines what constitutes a high quality BIM object for use with Level 2 BIM, with the right levels of information, appropriate geometry, and a consistent, structured, easy to use format.
 Find out more
 Related articles on Designing Buildings Wiki
- Asset information model.
- BIM articles.
- BIM glossary of terms.
- BIM nesting.
- BS 8541 Library objects for architecture, engineering and construction.
- Building component.
- Common data environment.
- NBS BIM library.
- NBS BIM object standard.
- Project information model.
- Step-by-step guide to using BIM on projects.