Level of Development (LOD)

The Level of Development in a BIM specifies what data must be in the model at what stage in the project development. The main specification is the American BIMforum document Level of Development (LOD) Specification parts I and II.

There is also a Danish standard developed by Digital Konvergens (DiKon) and BIM7AA called The Specification of Building Parts. The Danish specification breaks the Level of Development down into three components: Level of Reliability (LOR), Level og Geometry (LOG), Level of Information (LOI). This allows for the specification of a detailed model with little data (perhaps for rendering), or an information rich model with basic geometry (perhaps for facility management).