What LOD means
LOD stands for Level of Development. It describes how far an element in a model has been developed, and how far you can rely on it. It is not about how pretty the model looks. A rough placeholder can be drawn beautifully and still be LOD 100.
The scale most teams use comes from the AIA and the BIMForum, which publishes the LOD Specification. It has six levels.
| Level | In plain words | A wall, for example | Typical use |
|---|---|---|---|
| LOD 100 | A concept | A block or symbol showing a wall will be here | Early studies, massing |
| LOD 200 | Approximate | A wall with rough thickness and location | Schematic design |
| LOD 300 | Accurate and measurable | A layered wall with exact size, shape and position | Design development, construction documents |
| LOD 350 | Coordinated | LOD 300 plus how it connects to floors, supports and other trades | Coordination between trades |
| LOD 400 | Ready to fabricate | Detail needed to make and install it | Shop drawings, prefabrication |
| LOD 500 | Verified as built | Checked against what was actually built | Handover, facility management |
Which level should I ask for?
Pick the lowest level that serves the job the model must do. More detail costs more and makes models heavier. The common mistake is to write only “LOD 300” in a contract and assume everyone means the same thing.
- Planning approval or early design: LOD 100 to 200.
- Construction documents and quantities: LOD 300.
- MEP and multi-trade coordination: LOD 350.
- Fabrication of steel, ductwork or pipework: LOD 400.
- As-built records and operations: LOD 500.
LOD is not the same as accuracy or information
Three ideas are often mixed up:
- Level of Development (LOD): how developed and reliable the element is.
- Level of Information Need (LOIN): defined in ISO 19650 and EN 17412-1, it describes what information an element must carry for its purpose. It is set by the client or project.
- Level of Accuracy (LOA): from the USIBD, it states how closely a model must match a scan or survey. It matters on as-built and scan to BIM work.
Write it down
Whatever level you choose, put it in a table by element category, for example walls, structure, ducts and equipment, and attach it to the brief or BIM Execution Plan. Mixed levels are normal: architecture at LOD 300 and ducts at LOD 350 is fine, as long as everyone knows.
Quick questions
What is LOD 350?
LOD 300 plus the interfaces with other elements: how an element is supported or connected. It is the level most used for coordination between trades.
Is there a LOD 600?
Not in the BIMForum specification, which defines 100, 200, 300, 350, 400 and 500.
Published 14 October 2026 · Written by the Sactik team