Project Phases & Level of Detail (LOD)

Project Phases

In the construction industry, the design process is described by the phases of pre-design, conceptual design, design development, and final design. The building life cycle process is described by the phases of construction and building operation.

Typical Design Process of Buildings

Level of Detail (LOD)

In order to efficiently manage the process of working in a BIM workflow, the industry has adopted a formal language of describing the completeness of a digital model at a given point in time. This language is “Level of Development” (LOD).  LOD, in the BIM world, ranges from 100 (basic/conceptual) to 500 (highly detailed/precise). It is not unusual for levels of expected development to be part of the contract documents as described by the American Institute of Architect’s Building Information Modeling Protocol. 

LOD phases can be summarized as follows.

• LOD 100:  Modeled elements are at a conceptual point of development. Information can be conveyed with massing forms, written narratives, and 2D symbols. 

• LOD 200:  Modeled elements have approximate relationships to quantities, size, location, and orientation.  Some information may still be conveyed with written narratives.  

• LOD 300:  Modeled elements are explained in terms of specific systems, quantities, size, shape, location, and orientation. 

• LOD 400: Continuation of LOD 300 with enough information added to facilitate fabrication, assembly, and installation. 

• LOD 500: Modeled elements are representative of as installed conditions and can be utilized for ongoing facilities management.

It is worth mentioning that a relationship between LOD and design phases can be loosely established. However, it should be emphasized this relationship is not empirical. For instance a project as a whole may be in design development, but in the digital model, the building envelope system may be fully detailed with exact materials and thicknesses. More so, plumbing systems might be represented with single lines, not modeled geometries.  

Reference :BPA certificate