Level of Development (LOD) is one of the most useful — and most misunderstood — concepts in BIM. It defines how much geometric and information detail a model element should carry at a given project stage. Getting LOD right prevents both under-modeling (missing critical information) and over-modeling (wasting time and budget on unnecessary detail).
LOD 100 – Conceptual
At LOD 100, elements are represented as generic placeholders or massing. Overall size, volume and approximate location are known, but precise shape, material and system type are not. Typical use: early massing studies, zoning analysis, preliminary cost per square meter estimates.
LOD 200 – Approximate Geometry
Elements are modeled with approximate quantities, size, shape and location. Systems and materials may be indicated generically. Useful for schematic design, early coordination of major systems, and rough quantity take-offs.
LOD 300 – Precise Geometry
Elements are modeled with accurate size, shape, location and orientation. Non-geometric information (type, material, performance data) is attached as needed. This is the level most often required for construction documentation and detailed coordination. Dimensions can be taken from the model.
LOD 350 – Coordination Detail
An intermediate level used on many projects for interface and clash coordination. Elements include necessary connections, supports and clearances so that adjacent systems can be properly coordinated without yet reaching full fabrication detail.
LOD 400 – Fabrication Ready
Elements are detailed sufficiently for fabrication and assembly. This includes precise geometry, connections, shop-drawing level information and manufacturing data. Structural steel, precast concrete and complex MEP assemblies often reach LOD 400.
LOD 500 – As-Built / FM
The model reflects the actual constructed conditions. Geometry and data are verified against the completed works and are suitable for facility management, maintenance planning and future renovation design.
How to Choose the Right LOD
- Align LOD requirements with project phase and decision needs — not with “maximum possible detail”.
- Define LOD per element category in the BIM Execution Plan (BEP), not as a single number for the whole model.
- Consider who will use the information: designers, fabricators, site teams or facility managers.
- Balance modeling effort against the value of the information at that stage.
Over-modeling early in a project is one of the most common sources of wasted effort. Agree the LOD matrix with the client and design team before significant modeling begins.
Practical Tip
When requesting BIM services, specify both the geometric LOD and the information requirements (parameters, classification, COBie fields, etc.). Geometry alone is not enough for many downstream uses.
Need help defining an LOD matrix for your next project? Contact our team for a short consultation.