The initial decision in modeling an existing structure digitally is that of determining how detailed the model should be. The model used at the early stages of the renovation process may not have the same amount of data as that which will be used for multidisciplinary coordination or manufacturing.
This is where the requirement for Scan to BIM LOD comes into play. Level of Development (LOD) is the degree of development and accuracy that is required from each element of the model in order to fulfill its purpose. It makes it possible for architects, engineers, contractors, and BIM technicians to find an agreement concerning the type of information that should be captured in the model.
Selecting an appropriate LOD might prevent you from performing an effortful modeling unnecessarily, while at the same time ensuring that the end product meets your expectations.
Below is a guide to the following LODs: LOD 200, LOD 300, LOD 350, and LOD 400.
What Does LOD Mean in Scan to BIM?
Understanding Level of Development
The most effective BIM model is not necessarily the one with the most geometry. It is the one that contains the correct information needed to make the decisions required for the project.
Not sure what LOD you need? Contact our BIM experts. Establishing the use, elements, and coordination needs at an early stage will assist in selecting the right modeling strategy for your project. BIMForum’s LOD Specification is a useful reference for defining these requirements.
In Scan-to-BIM workflows, laser scanners collect visible conditions of the building as point clouds. BIM specialists proceed to create model elements based on this data and the defined level of detail (LOD).
Factors taken into account due to the required LOD include:
- Which elements of architecture, structures, and mechanical, electrical, and plumbing systems should be modeled.
- How precisely their geometry and placement have to be modeled.
- If any connections and interfaces require additional modeling.
- What amount of information would be necessary for coordination or installation.
- What elements can be left simple or outside the scope of the project.
LOD vs. Level of Detail
LOD may be used as a shortcut for Level of Detail in informal conversations. Yet, Level of Development is not just about visual detail but also the applicability and reliability of elements within the model.
Visually detailed models may not always be applicable for construction coordination. Model elements have to contain the needed information, and the limitations have to be known.
In case of existing building renovation projects, teams should determine the purpose of modeling, scope of the model, accuracy, and criteria of acceptance instead of simply LOD level.
LOD 200: Massing and Approximate Geometry
What LOD 200 Represents
Level of Detail 200 usually consists of items that can be recognized as systems, objects, or assemblies but are somewhat approximate.
Thus, there is no need for the exact size, shape, location, and orientation to be known. Instead, these features are estimated.
Typical Uses of LOD 200
It would be suitable in situations where teams are required to have a general overview of a structure and not necessarily all of the components accurately represented.
The uses for this can be found in situations like:
- Early studies on the feasibility of building renovations.
- Space planning and comparison exercises.
- Concept design exercises.
- Massing and visualization of structures.
- Assessing the availability of space.
In the example of renovating offices, it can be useful in helping the design team assess different room arrangements.
Limitations of LOD 200 for Existing Buildings
It is possible that approximate geometry does not contain enough detail to support precise coordination. In case of renovations, which require the use of accurate ceiling heights, clearance dimensions, or MEP routing, there might be a need for more refined model components.
Thus, LOD 200 can be used only if its restrictions correspond with the project goals. A model created for early planning should not necessarily be considered a reliable source of data for detailed installation planning.
LOD 300: Accurate Geometry for Design and Coordination
Level of Development (LOD) defines the level of development and reliability of BIM objects on an individual basis. LOD helps the project team define the content of the model element and its usage.
Level of Development Specification by BIMForum defines the industry standards regarding the definition of model element content and reliability. It also comprises LOD 250 in its version 2025.
It should be understood that LOD is not just a matter of visual detail. The geometry and definition of elements have to be defined for the project.
Geometry and Position of Model Elements
- LOD 300 shows certain parts that have a certain quantity, size, shape, position, and orientation based on the requirement agreement.
- In the Scan-to-BIM process, point cloud data will be used as the base for creating the existing architectural, structural, and visible MEP parts.
- According to the scope of work, the model might include:
- Walls, floors, ceilings, doors, and windows.
- Beams, columns, and other structural parts.
- Equipment and building services geometry.
- Element positions and sizes for further design development.
- Certain building parts for renovation planning.
LOD 300 for Renovation and Retrofit Projects
LOD 300 shows certain parts that have a certain quantity, size, shape, position, and orientation based on the requirement agreement.
In the Scan-to-BIM process, point cloud data will be used as the base for creating the existing architectural, structural, and visible MEP parts.
According to the scope of work, the model might include:
- Walls, floors, ceilings, doors, and windows.
- Beams, columns, and other structural parts.
- Equipment and building services geometry.
- Element positions and sizes for further design development.
- Certain building parts for renovation planning.
What LOD 300 Does Not Automatically Include
It is important to note that LOD 300 does not indicate that all concealed elements have been identified or that each model element has been independently verified.
The point cloud contains the surfaces that can be seen during scanning. Concealed elements such as pipes and voids may need further investigation or source information.
It is important to note that LOD 300 does not indicate that all concealed elements have been identified or that each model element has been independently verified.
The point cloud contains the surfaces that can be seen during scanning. Concealed elements such as pipes and voids may need further investigation or source information.
CRESIRE has published a related example describing how laser scan data can be developed into an LOD 300 model for design coordination. Read the laser scan to LOD 300 BIM model example to understand the relationship between reality capture, modeling scope, and design use.
LOD 350: Connections and Interfaces Between Systems
What Makes LOD 350 Different from LOD 300?
LOD 350 explains further the geometry of LOD 300 by adding more information on interfaces to other systems in the building.
It is important to note that the aim of this level of definition is not just an increased geometric detail. It is rather the creation of relationships and interconnections which will enable coordination.
This can include appropriate supports and interfaces depending on the agreed-upon scope.
Representing Interfaces Between Building Systems
Think about a current commercial building in which there is HVAC ducting going through a crowded ceiling area with beams, pipework, conduits, and lighting.
An LOD 350 model that has been created to an appropriate level may give further interface information and allow the coordination team to look at how these interfaces will fit together.
Examples of such coordination may be:
- Ducting interfaces with the structural beams.
- Pipework near other building services.
- Interconnections and surroundings of the equipment.
- Space required for access and maintenance.
- Interfaces between architecture, structure, and MEP systems.
What elements need to be included can be stated in the project specification. Not all LOD 350 models will include everything.
When LOD 350 Is Useful
LOD 350 can be considered when there is a need for greater coordination of interfaces than what LOD 300 offers.
Some cases could be complicated refurbishment projects, crowded plant rooms, service upgrades in buildings, and multidisciplinary design reviews.
But the use of LOD 350 doesn’t ensure that all clashes will be detected. Coordination also depends on the completeness of models, the latest revision, the right clash rules, and review by the relevant design disciplines.
LOD 400: Fabrication and Installation Detail
Fabrication-Oriented Modeling
LOD 400 could be appropriate for prefabricated assemblies or components that need detailed installation planning.
These would be:
- Prefabricated ductwork assemblies.
- Detailed mechanical or piping assemblies.
- Prefabricated structural assemblies.
- Installation-specific assemblies.
- Assemblies that need manufacturer or fabrication data.
The data needed will depend on the trade, fabrication process, and project specification.
Fabrication-Oriented Modeling
LOD 400 could be appropriate for prefabricated assemblies or components that need detailed installation planning.
These would be:
- Prefabricated ductwork assemblies.
- Detailed mechanical or piping assemblies.
- Prefabricated structural assemblies.
- Installation-specific assemblies.
- Assemblies that need manufacturer or fabrication data.
The data needed will depend on the trade, fabrication process, and project specification.
When LOD 400 May Be Necessary
LOD 400 will be appropriate only if there is a need to model those items that are related to manufacturing or installation processes. It is not automatically applied to every building survey or renovation.
A point cloud can be used to record existing conditions if visible, but it cannot provide all information on its own for the process of manufacturing. It might be required along with manufacturer’s specifications and approvals by engineers.
For these reasons, one needs to differentiate between modeling an existing item and creating a fabrication item.
Which LOD Should You Choose for Renovation, Facility Management, or Heritage Projects?
The right LOD depends on how the model will be used, which elements are included, and what information project stakeholders need.
Project use | Potentially suitable LOD | Main consideration |
Early planning and feasibility | LOD 200 | Approximate geometry may be sufficient |
Renovation design and existing-condition documentation | LOD 300 | Defined dimensions and positions |
Detailed multidisciplinary coordination | LOD 350 | Additional interfaces and connection information |
Fabrication and installation planning | LOD 400 | Fabrication-specific geometry and information |
This is a general guide, not a universal specification. Different elements within the same project may require different LODs.
LOD Requirements for Renovation and Retrofit
The initial stage of a renovation project usually starts from poorly documented plans and modifications. The LOD 300 can be the source of defined geometry for the development of design, while some MEPS/structural components can require LOD 350.
The key task is to define what parts of the project will require further modeling.
LOD for Facility Management
Models for Facility Management may focus on asset management, locations, equipment, and maintenance needs.
The highest LOD in terms of geometry may not necessarily be required.
Users have to determine the information that facility managers require and decide whether information about assets, equipment, and maintenance must be provided or not.
Special Considerations for Heritage Buildings
Historic structures tend to feature irregular geometry, non-standard construction, and vulnerable architectural details. Different criteria for documenting such structures can apply when compared to modern commercial buildings.
The modeling process depends on conservation criteria, scan coverage, importance of details, and purpose of using the model. There could be a need for extra detailing of some details but it may not be feasible for all the building parts.
How LOD Affects Scan-to-BIM Cost and Turnaround Time
Modeling Effort and Required Information
Increased modeling complexity could raise production and quality assurance burden if individual components require more complex geometries or more details on their interfaces.
At the same time, LOD is only one of the factors affecting project pricing and scheduling. Another ones include project building complexity, point clouds, discipline scope, deliverables, deadline, and more.
Possible effort influencing factors are:
- Project complexity: Complex geometries and crowded service areas would require more modeling work.
- Scope of disciplines included: Structural, HVAC, MEP, and any other disciplines would add more work.
- Quality of point cloud scans: Inadequate coverage or problems with registration could require investigation.
- Interface needs: Coordination would demand more detailed modeling.
- Deliverables: Revit models, CAD drawings, etc. would have to be prepared.
- Revisions: Changes in the scope agreed.
Defining Scope to Avoid Rework
Before modeling begins, clients and vendors should agree on the intended use, LOD by element or discipline, required file formats, exclusions, and acceptance criteria.
CRESIRE’s Scan to BIM modeling page provides information about its modeling workflow and deliverables.
A clearly defined scope helps teams avoid paying for unnecessary detail while reducing the risk of receiving a model that does not meet project requirements.
Example from a LOD 300 Project
From Laser Scan Data to a Coordination Model
How Laser Scan Data Creates an LOD 300 BIM Model for Design and Coordination by CRESIRE provides a workflow to translate point cloud data into a model that enables design and coordination.
This example illustrates one of the problems of existing buildings where the original drawings might not represent the current state of architectural, structural, or building services elements.
A scan-based workflow can assist in creating a reference for the current conditions and developing the model geometry based on the specified requirements.
Lessons for Projects Requiring LOD 350
Even though the provided example is for LOD 300 and not LOD 350, it provides a good starting point in that teams need to determine what the current geometry is before determining what needs interface details.
The next step for a project needing LOD 350 would be to identify the interfaces needed, determine if the source data for these is available, and set coordination criteria.
It is important to understand the difference between the two since a project is supposed to be described based on its deliverables, not its LOD number.
Choosing the Right Level of Development
The most effective BIM model is not necessarily the one with the most geometry. It is the one that contains the correct information needed to make the decisions required for the project.
Not sure what LOD you need? Contact our BIM experts. Establishing the use, elements, and coordination needs at an early stage will assist in selecting the right modeling strategy for your project.
FAQs About Scan to BIM Cost
What is point cloud data in building documentation?
Point cloud data is a collection of 3D coordinates captured using laser scanners. It represents visible building surfaces, including walls, floors, ceilings, columns, and exposed building services.
How does point cloud data help document existing buildings?
It captures the actual geometry of a building, helping project teams record dimensions, identify differences from old drawings, and prepare reliable documentation for renovation and retrofit work.
Can point cloud data replace existing building drawings?
Point cloud data can help verify and update existing drawings, but it does not automatically replace them. Drawings or models must still be created from the scan data according to project requirements.
What building elements can laser scanning capture?
Laser scanning can capture visible architectural elements, exposed structural components, and accessible MEP systems, such as ducts, pipes, and equipment. Hidden elements cannot usually be documented from the scan alone.
How is point cloud data used in renovation projects?
It helps teams understand existing dimensions, floor levels, clearances, and service locations before modifying a building. This supports design planning and can reduce uncertainty during renovation.
What are the limitations of point cloud data?
Obstructed areas, incomplete scan coverage, and registration errors can affect the usefulness of the data. Point clouds also do not directly reveal hidden services, material properties, or structural integrity.
Can point cloud data be converted into a BIM model?
Yes. Point cloud data can be used to develop an as-built BIM model in software such as Autodesk Revit. The model’s detail and included elements depend on the project’s scope and required LOD.
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