- 01LOD describes the content and reliability of a model element; it is not merely a measure of visual detail.
- 02LOD 300 (accurate geometry and position) and LOD 350 (with interfaces to other systems) are the workhorses of coordination.
- 03LOD 400 supports fabrication and assembly. LOD 500 records observed existing or as-constructed conditions and is not simply a higher rung than LOD 400.
- 04Specify LOD per element and per phase — this is the single biggest lever on BIM cost and value.
LOD — Level of Development — states what a model element contains and how reliably downstream teams may use it. It is not a visual-detail ladder and it does not automatically map one level to each design phase. Used well, LOD is the precise agreement that controls model purpose, cost, and reliance element by element.
The LOD levels
| LOD | Meaning | Typical use |
|---|---|---|
| 100 | Conceptual — symbolic, approximate | Massing, early feasibility |
| 200 | Approximate geometry, size, location | Schematic design |
| 300 | Accurate geometry, quantity, position | Design development, coordination |
| 350 | LOD 300 + interfaces with other systems | Multi-discipline clash coordination |
| 400 | Fabrication & assembly detail | Shop drawings, prefabrication |
| 500 | Observed existing or as-constructed condition; accuracy specified separately | Record models and asset information where required |
What LOD 500 means — and does not mean
Under the BIMForum framework, LOD 500 is not the next model-development step after fabrication-level LOD 400. It identifies an element whose existing or as-constructed condition has been observed in the field. The required measurement method and accuracy must be specified separately; calling a model “LOD 500” does not by itself define survey accuracy, completeness, or suitability for facilities management.
Choosing LOD by element and phase
You almost never need a single LOD across a whole model. Structure might be LOD 300 while a congested plant room is modeled to LOD 350 for coordination and a prefabricated riser to LOD 400. Specifying LOD per element (and per project phase) in your BIM Execution Plan is what stops you from either overpaying for unnecessary detail or under-modeling the areas that carry real risk.
The right detail in the right place
Spetia Engineering helps you specify LOD per system and phase, then delivers to it precisely — so coordination-critical areas get the detail they need and everything else stays lean.
Technical references
Primary standards and industry guidance used for definitions and design context. Project requirements and local codes always govern.
- 01
- 02
- 03ISO 19650-1: Information management using BIM — concepts and principlesInternational Organization for Standardization
