LOD 100 is the model's starting point. It is not a rough draft you improve later — it is a deliberate precision level that matches what architects actually know at schematic design. Every element in an LOD 100 model is there for a reason, and every element that is absent is absent for a reason.
Understanding what belongs at LOD 100 — and what does not — is one of the clearest ways to protect a project from early over-modeling and late-stage rework.
What Is LOD 100?
LOD 100 (Level of Development 100) represents building elements as conceptual massing geometry. It defines overall form, approximate size, and location. Nothing is manufacturer-specific. Nothing is dimensionally precise. The model communicates intent, not commitment.
The BIMForum LOD Specification defines LOD 100 as: elements may be represented by a symbol or other generic representation and do not satisfy the requirements for LOD 200. Information related to the element — such as cost per square foot — can be derived from other model elements, not from the element itself.
In other words: at LOD 100, location, size, and shape are conceptual, not accurate. The model communicates intent, not commitment.
In practice: if you are modeling a curtain wall at LOD 100, you are placing a surface that represents where the facade will be. You are not placing mullions, specifying panel types, or selecting a manufacturer system.
What an LOD 100 Model Contains
At LOD 100, the model holds only what can be determined at schematic design:
- Overall building footprint and massing volume
- Approximate floor-to-floor heights
- Gross facade surface area
- Approximate window-to-wall ratio (WWR)
- Approximate orientation of each facade face
- Conceptual panel module dimensions (for example, a 5-foot grid)
These are not guesses — they are decisions that define the project at the schematic level and directly affect budget ranges, zoning compliance, and early structural coordination.
What an LOD 100 Model Does Not Contain
Just as important is what LOD 100 deliberately excludes:
- Mullion profiles or framing geometry
- Panel materials or finish specifications
- Manufacturer-specific components or families
- Connection details or anchorage geometry
- Window type or glazing specifications
- Thermal or acoustic performance data
- Dimensions within ±1 inch (LOD 300 precision)
Including these at LOD 100 is not more thorough — it is a mistake. It ties decisions to unknowns, creates false precision, and forces rework when those assumptions prove wrong. On facade projects, that rework is measured in weeks.
A Concrete Example: 25-Floor Residential Tower at Schematic Design
A team is working on a 25-floor multifamily residential building with a glass curtain wall facade. It is week three of schematic design. The architect knows the massing, the approximate floor count, and the target window-to-wall ratio of 55%.
At LOD 100, the Revit model contains:
- A mass element representing the building envelope
- Four facade surfaces labeled by orientation
- A curtain wall system with a 5-foot conceptual module — no specific manufacturer
- Gross area per facade face: approximately 18,000 sq ft south, 12,000 sq ft east and west, 8,000 sq ft north
- A preliminary WWR of 55% derived from the grid
What the model does not contain: any specific panel system, mullion configuration, spandrel height, or window unit type. The structural engineer is working from the same massing model to size slabs. Nobody has committed to a curtain wall supplier.
This is correct LOD 100. The model is doing exactly what it is supposed to do.
What Decisions Get Locked In at LOD 100
LOD 100 locks fewer decisions than most architects expect — which is the point. What gets locked:
- Building orientation and massing form — everything downstream coordinates to this
- Approximate floor count and heights — affects structure, MEP, and vertical transportation
- Gross facade area — drives early budget ranges (cost per square foot of curtain wall)
- Conceptual module rhythm — sets the grid spacing that will be refined at LOD 200
What does not get locked: materials, suppliers, connection types, or specific panel configurations. Those decisions belong to later LOD levels — and making them at LOD 100 is a source of expensive rework.
What Breaks If You Skip LOD 100
The most common mistake is jumping from a rough sketch straight to LOD 200 or LOD 300 modeling. When that happens:
- The structural engineer coordinates to geometry that has not been confirmed
- The facade budget is based on specific panel types that may change at design development
- Zoning review happens against a model that commits to details the architect has not decided
- When the client changes the facade concept — which happens regularly — rework cascades through coordinated models
LOD 100 is protection. A clean LOD 100 model makes the schematic design phase legible to all consultants without locking them into decisions that have not been made yet.
What Breaks If You Over-Build LOD 100
The opposite problem is equally common: modeling at LOD 300 precision during schematic design. This happens when Revit's default curtain wall tools push architects toward detailed grid configuration before they are ready.
Consequences:
- Revit schedules generate false-precision data — panel counts and areas — that mislead the cost estimator
- The model creates an implicit commitment to a panel layout the team did not intend to finalize
- Every design iteration requires updating a fully detailed model, taking hours instead of minutes
The right model for the right phase. LOD 100 at schematic design keeps iterations fast and coordination accurate. For a full view of how LOD levels sequence through a project, see LOD in BIM: What LOD 100, 200, 300, and 400 Mean for Facade Projects.
LOD 100 and Facade Design
Facade systems are where LOD discipline matters most. A curtain wall at LOD 100 is a surface with a module concept. A curtain wall at LOD 300 has coordinated panel types, spandrel heights, and manufacturer-specific families. The difference in modeling time is measured in days. The difference in decision commitment is measured in months of rework if the design changes.
For facade teams specifically:
- LOD 100 supports zoning analysis — floor plate area, tower percentage, setback compliance
- LOD 100 supports early Light and Air compliance checks — approximate WWR and window-to-floor-area ratio
- LOD 100 supports preliminary cost ranges — gross area and system type are the key variables at this stage
What LOD 100 does not support: shop drawing generation, panel schedule production, or fabrication coordination. Those belong to LOD 300 and LOD 400, which come later in the workflow.
Does Kora Studio Work at LOD 100?
Yes. LOD 100 is Kora Studio's operating level.
Kora Studio is built for the design phase — the point in a project where facade geometry, module layout, and compliance metrics need to be explored quickly without committing to a specific supplier system. The Grid Editor lets architects define facade grids with formula-driven dimension fields. The Calculations and Scheduling module produces Light and Air values and panel area data directly from the LOD 100 model, feeding into Revit schedules without requiring detailed LOD 300 families.
Kora does not operate at LOD 200, LOD 300, or LOD 400. It is designed specifically for the LOD 100 design phase — to make it accurate, fast, and decision-ready so the handoff to the next level is clean.
See how architects and BIM managers use Kora Studio to complete facade design at LOD 100 in a fraction of the time standard Revit workflows require.
Frequently Asked Questions
Is LOD 100 the same as a massing model? Largely yes, but not exactly. An LOD 100 model can include more than pure massing — it may define approximate floor heights, a conceptual facade module, or an approximate panel count. The key constraint is that nothing in the model exceeds what is actually known at schematic design.
Can you generate a cost estimate from an LOD 100 model? Yes — at the right precision. LOD 100 supports order-of-magnitude budget estimates based on gross facade area and system type. It does not support detailed line-item quantity takeoffs. That is what LOD 300 models are for.
Does Kora Studio work at LOD 100? Yes. LOD 100 is Kora's primary and only operating level. Kora is not designed for LOD 200, LOD 300, or LOD 400 work. It handles facade grid definition, panel area calculations, and Light and Air metrics at the schematic design phase.
What is the difference between LOD 100 and LOD 200? LOD 200 adds approximate geometry — dimensions become more precise, panel types are represented (though still generic), and spatial coordination between disciplines begins. See LOD 200 in BIM: Approximate Geometry and What It Commits You To for the full breakdown.
Do all BIM Execution Plans require LOD 100 documentation? Most BEPs define LOD requirements by element and phase but do not always specify LOD 100 explicitly. In practice, the schematic design submission implicitly delivers LOD 100. If your BEP skips LOD 100, the project typically jumps straight to LOD 200 at the start of design development. See What LOD Do Architects Actually Need for a phase-by-phase breakdown.
Book a demo to see how Kora Studio handles facade design at LOD 100.
