Key Takeaways
- RVT is the native Revit file format used for BIM model development.
- IFC provides an open approach to BIM interoperability between different software platforms.
- NWC is associated with Navisworks coordination and cached model data.
- DWG is a widely used CAD format for drawings and geometry exchange.
- No single format is appropriate for every BIM workflow.
- RVT is generally best for native Revit authoring and development.
- IFC is useful for openBIM and cross-platform model exchange.
- NWC is useful for Navisworks-based coordination and clash detection.
- DWG remains valuable for CAD drawings, surveys, details, and geometry.
- File conversion should be planned around the information the receiving team needs.
- BIM file exchange should include clear naming, coordinates, revisions, standards, and quality checks.
Building Information Modeling (BIM) relies on digital files to create, exchange, coordinate, and manage project information. Among the most common BIM file formats are RVT, IFC, NWC, and DWG. Each format serves a different purpose, and choosing the right one can affect model coordination, data exchange, collaboration, and project workflows.
For architects, engineers, contractors, BIM coordinators, and project owners, knowing the difference between these formats is important. An RVT file may be ideal for working directly in Revit, while IFC can support openBIM exchange between different platforms. NWC files are useful for Navisworks coordination, while DWG remains widely used for CAD drawings and 2D documentation.
What Are BIM File Formats?
BIM file formats determine how building models, drawings, geometry, and project information are stored and exchanged between software applications. Unlike a simple image or PDF, BIM-related files can contain information about building elements, dimensions, materials, relationships, classifications, and other project data.
The right format depends on what you need to accomplish. A native authoring format is generally better when teams need to continue editing a model in the same software. An open exchange format can be more useful when different disciplines or companies use different BIM platforms. Coordination formats may be optimized for reviewing combined models rather than creating design content.
RVT: Revit Project and Model Files
The native file format of Autodesk Revit is called RVT and it stores information about the building or structure described with the help of this software. It contains all the architectural, structural, mechanical, electrical, plumbing, and multidisciplinary elements and relations between them needed for the construction of the object.
When Should You Use RVT?
RVT is typically best when the receiving team is going to work in Revit and needs access to the native model data. For example, an architectural group may send an RVT model to the structural group for coordination purposes, enabling the structural group to attach the architectural model to their own.
RVT is also beneficial for the continuous editing of native Revit elements beyond simple coordination of model geometry. It offers a direct connection to the Revit authoring environment, making it beneficial throughout the design process and multidisciplinary building information modeling workflows.
Advantages and Limitations of RVT
The biggest advantage of using RVT is that it is native to Revit. It retains the structure and information necessary for continuing to develop in Revit and supports multidisciplinary coordination of different RVT models.
The main disadvantage of the software is its close connection to Revit. The file created by the application will not be properly used by another BIM software not connected to Revit. That is why IFC formats remain relevant for years.
IFC: Open BIM and Interoperability
The IFC (Industry Foundation Classes) is an open standard neutral to all software vendors’ BIM formats, allowing the exchange of information contained in the models between different software. With this software, it is possible to establish collaboration between various participants in the construction of buildings, such as architects and engineers, and carry out projects using different software.
When Should You Use IFC?
The IFC is a great choice if you have different software that needs to exchange information in BIM. The example would be collaboration between an architectural team using Revit and a structural team using another BIM software. The solution would be an IFC export that both parties can work with.
Another advantage of using IFC is its application in cases when an openBIM deliverable is needed or long-term accessibility to the model information is desired, independent of a particular software. Therefore, it can be concluded that IFC is beneficial for multidisciplinary coordination and information exchange.
Advantages and Limitations of IFC
The primary benefit of using IFC is interoperability. It allows for the exchange of building information modeling data between different software packages, which is especially valuable when working in an openBIM environment or when collaboration between different technologies is required.
IFC should not be regarded as a universal solution for using native model files. During the process of exchange, there is a possibility that not all data will be correctly transferred. Therefore, geometry, properties, relationships, and classifications should be reviewed during and after exchange from the authoring tool.
NWC: Navisworks Cache Files
NWC (Navisworks Cache) is a file format used by Autodesk Navisworks for model coordination, visualization, and clash detection. Unlike RVT, it is designed for coordination rather than primary model authoring.
When Should You Use NWC?
NWC is the best choice when project teams are using models for Navisworks coordination. Architectural, structural, MEP, and other models can be prepared for coordination and brought into a Navisworks environment.
This enables NWC to serve as a multidisciplinary coordination platform for clash detection, constructability, and model visualization. The native model is used as the source of record for design changes, while the coordination environment makes use of the appropriate cached representation.
Advantages and Limitations of NWC
NWC can help the review process during the coordination workflow to make it more efficient since it caches model information for Navisworks. It is very beneficial when there is a necessity to consolidate multiple discipline models for the review.
However, NWC is primarily a coordination tool, rather than a design-authoring format, and a change to the original Revit model will require a change in NWC, however, it should be remembered that NWC is not an alternative to native RVT files, and changes should be made in the program in which they were created.
DWG: CAD Drawings and Design Exchange
DWG is a popular CAD file format used in AutoCAD and other computer-aided design software. While DWG is not a BIM format itself, it is closely related to BIM and CAD projects due to the prevalence of CAD drawings in many industries.
DWG files can store 2D and 3D models and are commonly used to represent site plans, details, surveys, as-built drawings, or other information typically found in CAD drawings. The BIM team often needs to reference these drawings when constructing their model or when sharing information between CAD and BIM software.
When Should You Use DWG?
DWG is appropriate for sharing CAD-based drawings or geometry in particular. For instance, a surveyor might supply a construction site plan in DWG format for reference by an architectural or civil BIM team.
DWG can also be used to represent existing condition information or 2D drawings. Much existing built work has extensive CAD documentation, meaning that a BIM team may need to deal with such information during the development of new projects or during retrofits.
Advantages and Limitations of DWG
DWG is a widely used file format in the architecture, engineering, construction, manufacturing, and design industries. It is a great exchange format for computer-aided design (CAD) data due to its prevalence in the industry.
Its primary limitation is that it is a CAD format and not a building information modeling (BIM) format. In other words, while a DWG file allows for an extensive range of geometric representation, it lacks the ability to represent the full spectrum of information contained within a BIM model.
RVT vs IFC vs NWC vs DWG
The four formats serve different purposes within the AEC industry. RVT is a native authoring format, IFC is primarily an open exchange format, NWC supports Navisworks coordination, and DWG is primarily used for CAD drawings and geometry exchange.
| File Format | Primary Purpose | Typical Software | Best Used For |
|---|---|---|---|
| RVT | Native BIM modeling | Revit | Design and model development |
| IFC | Open BIM exchange | Multiple BIM platforms | Interoperability |
| NWC | Model coordination | Navisworks | Coordination and clash detection |
| DWG | CAD drawing exchange | AutoCAD and CAD platforms | 2D/3D drawings and CAD data |
The choice should therefore depend on what the receiving team needs to do with the file. A project may use several formats at the same time rather than selecting only one.
RVT vs IFC: Which One Should You Use?
RVT is generally preferable if the majority of participants work in Revit and need to continue collaborating on the native model. It offers the possibility to work in a familiar environment and directly edit Revit elements.
In contrast, IFC is appropriate when the building data need to be shared in a software-independent way or when the receiving party does not use Revit. Both formats can be used in combination with each other when a project involves RVT elements in native Revit format and IFC objects to be shared externally.
IFC vs NWC: What Is the Difference?
IFC and NWC can be applied in multidisciplinary coordination, but they are used in different aspects. The first one is IFC (Industry Foundation Classes), which is used for collaboration between BIM applications, whereas NWC (Navisworks Coordinate) is related to Navisworks coordination and caching.
Thus, it is possible to use both IFC and NWC for multidisciplinary coordination. They are intended for different areas of model exchange or coordination so that there is no particular code replacing the other in a specific application.
RVT vs DWG: What Is the Difference?
The main difference between RVT and DWG is that the former is used for BIM modeling in Revit, while the latter is a CAD vector graphics format. An RVT file contains a building or architectural model with its specific properties and data. On the other hand, a DWG file is primarily related to CAD drawings or computer-aided design.
Therefore, for BIM authoring and detailing, it is better to use the first option, while for CAD drawings, survey data, 2D models, and other data, the second option is better.
When to Use Each BIM File Format
Use RVT when there is a necessity for a native Revit model that can be further edited, coordinated, or developed in Revit. In this case, RVT is suitable for design development and multidisciplinary collaborative work in Revit.
Use IFC to exchange information between different BIM authoring tools and for openBIM collaboration. Apply NWC for Navisworks-based reviewing, coordination, visualization, or clash detection tasks. Use DWG for exchanging CAD drawings, survey data, 2D documents, and graphics.
BIM File Formats and Model Coordination
Consider file format selection in cases where a design is produced using multidisciplinary tools. For instance, architectural, structural, MEP engineering, civil, and fabrication teams often use different software packages. Each of these groups has its own requirements for model exchange.
In such cases, establishing a set of rules for file exchange is even more relevant than developing a standard. If individual steps are not properly coordinated, critical data may be lost, references may be broken, incorrect geometry imported, or unnecessary rework triggered. Hence, the BIM coordination plan should stipulate what format is to be used for exchange between what software, how often the models should be exchanged, and how changes should be managed.
BIM File Formats and Clash Detection
Clash detection depends on bringing multiple discipline models into a common coordination environment. The quality of the resulting analysis depends partly on how those models are exported, imported, and maintained.
NWC files can support Navisworks coordination workflows, while IFC can support model exchange between different BIM applications. RVT files may remain the authoritative native models for Revit-based disciplines, allowing teams to make design changes in the appropriate source environment.
BIM File Conversion: What Should You Consider?
Converting one file format into another can be useful, but conversion should not be treated as a completely lossless process. Before converting a BIM model, determine what information the receiving team actually needs and which elements must remain editable or structured.
If the recipient only requires 2D drawing information, DWG may be sufficient. If interoperable BIM information is required, IFC may be more appropriate. If the model is being prepared for Navisworks coordination, NWC may be suitable. After conversion, important geometry, coordinates, properties, classifications, and references should be checked against the original model.
Best Practices for BIM File Exchange
A successful BIM file exchange process begins with clear project standards. Teams should establish naming conventions, coordinate systems, file versions, exchange schedules, model origins, and required deliverables before model sharing begins.
It is also important to maintain a clear distinction between source files and exchange files. The native RVT model, for example, should remain controlled by the team responsible for authoring it, while IFC or NWC files can be issued for specific coordination purposes. Every exchanged model should then be reviewed after import to confirm that the required information transferred correctly.
Common Mistakes When Choosing BIM File Formats
Avoid common BIM file format mistakes by choosing the right format for modeling, coordination, exchange, and project data management.
Assuming one format fits every project:
Native authoring, coordination, and drawing exchange files serve different purposes. Using the wrong format can create unnecessary compatibility issues.
Converting files without defining requirements:
Determine what information must be preserved before converting a model. Geometry may transfer successfully while model intelligence, properties, classifications, or relationships are lost.
Ignoring project coordinates:
Maintain consistent coordinate systems when exchanging models to prevent alignment and positioning problems.
Using inconsistent units:
Confirm that all files use compatible measurement units before importing or linking them.
Poor revision control:
Clearly track file versions and revisions to prevent teams from coordinating outdated models.
Inconsistent naming conventions:
Use standardized file and model names so project teams can quickly identify the correct files.
How BIM Modeling Services Support File Coordination
Professional BIM modeling requires more than creating a three-dimensional representation of a building. Models must be structured, coordinated, documented, and delivered in formats appropriate to the project’s requirements.
A BIM service provider may work with native Revit models, IFC exchanges, Navisworks coordination files, CAD drawings, and other project deliverables depending on the scope. Understanding these formats helps ensure that each model is delivered in a form that supports the client’s software, coordination requirements, and downstream construction workflow.
Conclusion
BIM file formats shape how project information moves between authoring, coordination, and construction teams. Choose the format around the receiving team’s next task and the data that must survive the exchange.
RVT works best for native Revit modeling, IFC for cross-platform exchange, NWC for Navisworks coordination, and DWG for CAD drawings and geometry. Most projects use several formats together. Strand-Co’s BIM and modeling services help teams define a controlled exchange workflow and deliver models suited to each downstream use.
Frequently Asked Questions
What is the most common BIM file format?
There is no single BIM format that is best for every project. RVT is widely used for Revit-based BIM authoring, IFC is important for openBIM interoperability, NWC is common in Navisworks coordination workflows, and DWG remains widely used for CAD drawings and geometry exchange.
Is RVT better than IFC?
Neither format is universally better. RVT is generally better when teams need to work directly with a native Revit model, while IFC is more suitable when model information needs to be exchanged between different BIM platforms.
What is an NWC file used for?
NWC is a Navisworks Cache file used primarily in Navisworks-based model coordination and review workflows. It can help bring discipline models into a coordination environment for visualization and clash detection.
Is DWG a BIM file?
DWG is primarily a CAD file format rather than a complete BIM format. However, it plays an important role in BIM workflows because teams frequently exchange CAD drawings, survey information, and geometry through DWG.
Can Revit open IFC files?
Revit supports IFC interoperability. The exact information retained during IFC exchange can depend on the IFC version, export settings, and the nature of the model, so imported files should be checked after exchange.
Can RVT files be used in Navisworks?
Yes. Revit models can be brought into Navisworks for coordination workflows. Depending on the workflow, Navisworks can use cached representations such as NWC files.
Which BIM format is best for coordination?
The answer depends on the coordination environment. NWC is particularly useful for Navisworks-based coordination, while IFC can be valuable when models originate from different BIM platforms.
Which format should I request from a BIM service provider?
Ask for the format that matches your intended workflow. If you need an editable Revit model, RVT may be appropriate. If you need cross-platform BIM exchange, IFC may be preferable. For Navisworks coordination, NWC can be useful, while DWG is suitable for CAD drawings and geometry.
