LOD 300 is where design decisions become contractual commitments. The model at LOD 300 is precise, specific, and coordinated — construction documents are produced from it, consultants coordinate against it, and the owner and contractor rely on it for pricing and scheduling. It is also the boundary of the architect's responsibility. What comes after LOD 300 belongs to someone else.
Understanding what LOD 300 requires — and what it explicitly does not include — is one of the most important distinctions in BIM practice on facade projects.
What Is LOD 300?
LOD 300 (Level of Development 300) represents building elements with precise quantity, size, shape, location, and orientation. Components are modeled as specific systems — not manufacturer-specific in every case, but specific enough that the design intent is fully communicated and construction documents can be produced directly from the model.
The BIMForum LOD Specification states: at LOD 300, the model element is modeled as a specific system, object, or assembly in terms of quantity, size, shape, location, and orientation. Non-graphic information may also be attached to the model element.
Dimensions at LOD 300 are accurate within ±1 inch. Panel types, materials, and system configurations are specified. The model is coordinated with structure, MEP, and other disciplines. This is the deliverable that architects hand to the contractor at the construction documents phase.
What LOD 300 Contains That LOD 200 Does Not
Moving from LOD 200 to LOD 300 means resolving everything that was approximate and generic:
- Precise panel dimensions — confirmed with structural, within ±1 inch
- Specific material designations — glass type, panel finish, frame color
- Coordinated structural reveals and slab edge conditions
- Specific curtain wall system type — unitized, stick, or structural glazing
- Mullion and transom locations within the panel grid
- Spandrel zone heights confirmed against floor slab elevations
- Opening sizes coordinated with MEP rough-in locations
- Panel schedule with accurate counts and area by type
At LOD 300, every element in the model is intentional and specific. An architect reviewing the Revit properties panel for an LOD 300 curtain wall panel sees: panel type (vision or spandrel), exact width and height, material (e.g., 1-inch insulated glass, clear low-e), floor designation, and orientation. Nothing is generic.
What LOD 300 Does Not Contain
LOD 300 stops short of fabrication detail. It does not contain:
- Manufacturer part numbers or shop codes
- Connection hardware specifications (bolt sizes, weld types, torque values)
- Manufacturing tolerances or assembly sequences
- Shop drawings or fabrication packages
- Anchorage and embed details coordinated to structural shop drawings
These belong to LOD 400 — the fabricator's model. Adding them to the architect's LOD 300 model is not more thorough. It is a category error that creates liability, wastes time, and produces detail the architect is not qualified to guarantee.
LOD 300 vs LOD 350
Some BIM Execution Plans distinguish LOD 350 as an intermediate level between LOD 300 and LOD 400. LOD 350 adds interface information — how elements connect to and interface with other building systems. For facade projects, LOD 350 typically means:
- Curtain wall anchor locations coordinated to structural embed locations
- Perimeter sealant joint conditions between curtain wall and adjacent cladding
- Flashing and waterproofing interfaces at floor slab conditions
LOD 350 is sometimes the architect's responsibility, sometimes the facade consultant's. Confirm with your BEP which discipline owns each LOD 350 element. Not all projects use LOD 350 — it depends on project complexity and contractual requirements.
LOD 300 as a Contract Deliverable
Most BIM Execution Plans assign LOD 300 to the architect of record at the construction documents phase. This assignment carries contractual weight. When the BEP says the architect delivers LOD 300, it means:
- The architect's model is precise enough for contractor pricing
- The architect has coordinated with all consultants against this geometry
- The owner and contractor can rely on the model for construction scheduling
- Any change to the geometry after LOD 300 delivery triggers a formal change process
The boundary between architect and fabricator runs between LOD 300 and LOD 400. The architect delivers LOD 300. The fabricator advances it to LOD 400 — adding part numbers, connection details, and manufacturing data. See LOD 300 vs LOD 400: Where Facade Design Ends and Fabrication Begins for a detailed breakdown of that handoff.
What Breaks When an Architect Delivers LOD 200 Instead of LOD 300
A common problem on facade projects: the architect's construction documents are produced from an LOD 200 model with approximate geometry. This creates:
- RFIs from the contractor who cannot price from approximate panel sizes — panel counts are off, area calculations do not hold
- Coordination conflicts when structural shop drawings come in and the facade geometry does not align with confirmed slab edges
- Change orders when the fabricator identifies that the model does not reflect the actual panel configuration
- Schedule delays because the fabricator cannot begin shop drawing production from an approximate model
LOD 300 is not over-modeling — it is the minimum level at which construction documents can be trusted.
What Breaks When an Architect Produces LOD 400 Instead of LOD 300
The opposite problem is equally costly. Architects who model at LOD 400 during construction documents are doing the fabricator's job — and doing it too early:
- The model includes manufacturer-specific connection details that change when the actual fabricator is selected
- Design approvals come in after the model is detailed to fabrication precision — triggering rework across hundreds of panels
- The architect carries liability for fabrication-level decisions they are not equipped to guarantee
- Modeling time balloons — LOD 400 detail in a facade model can triple the hours required compared to LOD 300
The right deliverable at the right phase. LOD 300 for construction documents. LOD 400 for the fabricator, after design is approved and the supplier is selected.
Does Kora Studio Work at LOD 300?
No. Kora Studio operates at LOD 100 only.
LOD 300 is the architect's construction documents deliverable — precise families, coordinated geometry, material specifications. That work is done in standard Revit, coordinated with consultants, and checked against structural and MEP drawings. Kora is not part of that workflow.
Kora's role is the phase before LOD 300: the schematic design phase at LOD 100, where facade grids are defined, panel modules are explored, and Light and Air metrics are validated. By the time the project reaches LOD 300, the design decisions Kora supports — module layout, panel count, compliance metrics — are already confirmed. Kora produces the LOD 100 baseline that LOD 300 modeling is built on.
See Kora Studio Features for what the tool does at LOD 100, and Kora Studio Use Cases for how design teams use it in practice.
Frequently Asked Questions
What is the difference between LOD 300 and LOD 400? LOD 300 is the architect's precise deliverable — specific materials and geometry, but no fabrication detail. LOD 400 adds manufacturer part numbers, connection hardware, manufacturing tolerances, and assembly sequences. LOD 400 is the fabricator's model, not the architect's. See LOD 400 in BIM for the full breakdown.
Does Kora Studio produce LOD 300 output? No. Kora Studio operates at LOD 100. It does not produce LOD 300 families, coordinated drawings, or construction document-ready geometry. LOD 300 is produced using standard Revit families and the project's BIM coordination tools.
Is LOD 300 required on every BIM project? On most commercial projects, yes — either explicitly required by the BEP or implied by the construction document deliverables. Projects using a design-build or integrated delivery model may define different LOD milestones, but the precision level corresponding to LOD 300 is typically required before the contractor can begin procurement.
What is LOD 350, and is it the architect's responsibility? LOD 350 adds interface information — how building systems connect to and coordinate with each other. Whether the architect, facade consultant, or another party owns LOD 350 elements depends on the BEP. On complex facade projects, the facade consultant typically owns LOD 350 for the curtain wall system.
How do I know which LOD level is appropriate for my project phase? Your BIM Execution Plan should specify LOD requirements by element and phase. For a general guide, see What LOD Do Architects Actually Need for a phase-by-phase breakdown of LOD requirements for facade projects.
Book a demo to see how Kora Studio handles the LOD 100 phase before LOD 300 work begins.
