When drafting a contract or building execution plan, specifying the required Level of Development (LOD) is crucial. LOD defines the clarity, geometry, and attribute data loaded into each model element at different project milestones.
The LOD Scale Explained
- LOD 100 - Conceptual Design
- Elements are represented as basic symbols or conceptual volume outlines without specific location or sizing parameters.
- LOD 200 - Schematic Design
- Elements are modeled with general quantities, shapes, and location paths. Suitable for basic spatial planning.
- LOD 300 - Detailed Design
- Elements are represented as specific systems with precise dimensions, geometries, material parameters, and locations.
- LOD 350 - Spatial Coordination
- Includes specific connections, brackets, anchors, and interfaces needed to coordinate overlapping systems.
- LOD 400 - Fabrication Ready
- Detailed models featuring weld specifications, joint splits, and assembly details ready for offsite fabrication shops.
- LOD 500 - As-Built Record
- Field-verified models matching exact built locations, loaded with maintenance manuals and operations codes.
Why Specifying LOD Protects Your Project
Clearly defining LOD targets prevents trade disputes. Subcontractors know exactly when their systems must be fully detailed, preventing coordinate drift during coordination meetings.