BIM LOD – Level of Development vs. Level of Detail

Level of Detail is how much detail is included, or to be included,  in the model element, an “input”

Level of Development is the degree to which the element’s geometry can be relied upon by users…. an “output”.

First its important do know that there are varying Level of Development definitions.  For example,the  AIA’s Digital Practice
Documents include revised LOD definitions.  The AIA appears to allow the BIMForum to utilize the AIA’s LOD definitions.  Thus the BIMForum LOD Specification is  identical to those published in the AIA’s updated Digital Practice Documents, except that there is a LOD 350 and there is no LOD 500.

Here are the AIA LOD definitions:

LOD 100 The Model Element may be graphically represented in the Model with a symbol or other
generic representation, but does not satisfy the requirements for LOD 200. Information
related to the Model Element (i.e. cost per square foot, tonnage…