The short answer
Ask for LOD 300 when you need a model you can measure from, LOD 350 when trades must coordinate around it, and LOD 400 only when a fabricator will build from it. Most outsourced Revit work sits between LOD 200 and 350.
Each level at a glance
| LOD | What the element is | Typical use |
|---|---|---|
| 100 | A symbol or mass showing that something exists | Concept, area and massing studies |
| 200 | A generic object with approximate size, shape and location | Schematic design |
| 300 | A specific object with accurate size, shape, location and orientation | Design development, measured drawings, quantities |
| 350 | LOD 300 plus the interfaces with other systems (supports, connections, clearances) | Construction documents and trade coordination |
| 400 | Enough detail to fabricate and install | Shop drawings and fabrication |
| 500 | Field-verified as built | Handover and facility management |
LOD 100 to 400 follow the BIMForum LOD Specification. BIMForum does not define LOD 500, because it describes field verification rather than model progression.
LOD is set per element, not per model
A model is never "LOD 300" as a whole. A good BIM Execution Plan lists the LOD for each element type at each stage: for example walls at 300, structural framing at 350, furniture at 200. When you send us a project, tell us what the model is for and we propose an element table.
Where MDG works
We model at LOD 200, 300 and 350. We do not produce LOD 400 fabrication models or shop drawings.
Questions
What is the difference between LOD 300 and LOD 350?
LOD 300 places an element accurately. LOD 350 adds how it meets other systems, such as supports, connections and clearances, which is what trades need to coordinate.
Is LOD the same as Level of Detail?
No. Level of detail is how much geometry is drawn. Level of Development is how much you can rely on the element's geometry and information.
Does LOD 500 exist?
It is widely used for field-verified as-built models, but the BIMForum specification does not define it.
Which LOD should I ask for in a CAD to BIM conversion?
LOD 300 for most conversions. Ask for 350 if the model will be used for clash detection.