When to use: Planning how much modeling detail (Level of Development) each discipline should carry at each project phase. Modeling too little too late makes clash detection meaningless; modeling too much too early wastes hours on geometry that will change. Click any cell to set that discipline/phase's target LOD.
| Discipline | Schematic Design | Design Development | Construction Docs |
|---|---|---|---|
| Architectural | |||
| Structural | |||
| Mechanical | |||
| Electrical | |||
| Plumbing |
Level of Development (LOD) defines how much geometric and information detail a BIM model element carries at a given project phase, using the AIA/BIMForum LOD framework (100 through 400). This tool plans a target LOD per discipline per phase, flags cases where planned detail regresses between phases, and gives a quick reference for what each LOD level means.
Modeling every duct fitting and conduit bend at full fidelity from day one is often wasted effort at early design stages, when the design itself is still likely to change substantially. Most firms model to a level of development appropriate to the project phase, with MEP routing getting progressively more detailed as the design moves from schematic through design development into construction documents.
Clash detection is only as useful as the geometry available to clash. If MEP systems are still at LOD 100-200 (generic or approximate) when the project reaches the phase where coordination is supposed to happen, there is nothing precise enough to actually clash — coordination meetings become a formality rather than catching real problems. The mechanical room and above-corridor-ceiling zones, where systems from multiple disciplines converge, are exactly where undersized LOD produces false-negative coordination.
LOD 100 is conceptual massing with no specific geometry. LOD 200 is approximate geometry — generic systems with approximate size, shape, and location. LOD 300 is precise geometry with specific size, shape, location, and quantity. LOD 350 adds interfaces with other building systems, making it coordination-ready. LOD 400 is fabrication-ready, detailed enough for shop drawings and installation.
No — architectural and structural elements are often modeled to higher LOD earlier since their geometry stabilizes sooner, while MEP routing typically lags behind at lower LOD until design development, when equipment selections and routing decisions are made.
Generally LOD 300 or higher for the systems being coordinated — clash detection against LOD 100-200 geometry (generic placeholders) produces mostly false positives or misses real conflicts, since the modeled geometry doesn't yet reflect actual size, routing, or location.
Try our BIM, CAD & Digital Design Studio
More calculators, simulators, and guides for this discipline.