“Level of Development” (LOD) describes how far a model element has been developed — how reliable its geometry and information are for other people to use. Specifying the right LOD for each element is the single most effective way to keep a BIM scope, schedule and fee under control.
LOD is about reliability, not just detail
LOD is often confused with “level of detail”. Detail is how much an element looks like the real thing; development is how much the team can rely on its size, location and data.
The levels at a glance
- LOD 100 — conceptual. A symbol or massing that shows something exists. Useful for area and early cost studies; not for measurement.
- LOD 200 — approximate. Generic elements with approximate quantity, size, shape and location.
- LOD 300 — precise. Specific elements whose quantity, size, shape, location and orientation can be measured directly from the model.
- LOD 350 — coordinated. LOD 300 plus the parts needed to interface with other systems — supports, clearances and connections. This is where clash detection becomes meaningful.
- LOD 400 — fabrication. Enough detail and accuracy to fabricate and install the element.
- LOD 500 — field verified. Elements verified on site to represent the as-built condition.
Use an LOD matrix, not a single number
A project is rarely “LOD 300”. Structure may be at LOD 350 while furniture stays at LOD 100. An LOD matrix lists each element category against each stage and states the required LOD and the responsible party.
Our BIM and federated model coordination team can help you prepare an LOD matrix at kick-off, or model to the one you already have.
