The design technique of the BIM is based on the standards of accuracy. They operate in two planes, one for the accuracy of the model geometry and it is called “Level of Development” in short LOD, and the accuracy of the information associated with “Level of information” in short LOI. This division has allowed some general standards of accuracy to be introduced into the design technique. These definitions are based on a standard prepared by the AIA (American Institute of Architects) named AIA G202-2013 Building Information Modeling Protocol Form.
Brief description of the LOD accuracy
LOD 100 – the model element is represented by a symbol or a general approximate shape and approximate location
LOD 200 – the element is represented by a symbol or a generally solid, this accuracy allows you to define the required cubic capacity for objects. Ability to adjust functional and operational assumptions.
LOD 300 – The model element is represented by specific objects and systems, and you can count the total amount and volume, and you can perform some measurements based on the model. This level allows you to create preliminary analyzes to optimize, improve model quality, and verify building architectural values. This accuracy can be compared to the accuracy of the construction design
LOD 350 – a model element is represented by specific objects and systems, and the number and volume of objects and systems can be calculated from the model, and the measurement and coordination of other elements can be performed. The model includes support elements or joints.
LOD 400 – the model element is represented by specific objects and systems with details of the assembly and production information, the exact quantity and volume can be calculated from the model, and the measurement and coordination of other elements can be performed.
LOD 500 – the model element is represented by the actual model