Cross-Software IFC
Model Comparison

This tool compares differences between two structural IFC models.

You can upload two IFC models exported from different software, such as an Archicad IFC from the architect and a Revit, ETABS, or SAP2000 IFC from the structural engineer. The system helps identify section, position, angle, shape, and length differences in beams, columns, and other structural members.

In short, it helps you find inconsistencies between two models before drawing production, model coordination, or model exchange.

Most IFC comparison tools are mainly used to compare different versions of the same model, such as checking which members were added, deleted, or modified.

These tools usually rely on internal IFC GUIDs to determine whether two members are the same object, which makes them more suitable for version comparison within models generated by the same software.

However, in real BIM coordination, IFC models exported from different software such as Archicad, Revit, ETABS, and SAP2000 often have:

• Completely different GUIDs
• The same beam split into multiple members
• Different geometry representations
• Different modeling habits between software

IFC Compare does not rely on GUIDs. Instead, it first analyzes each member’s axis, geometry, spatial position, length, and section information to determine which members actually represent the same structural member, then compares their differences.

In other words, this tool is designed to solve cross-software model coordination, not just simple model version comparison.

This tool is useful when architectural and structural models need to be checked against each other.

For structural engineers, it can be used before drawing production to compare IFC files exported from Revit and ETABS / SAP2000, helping confirm whether beam and column sizes and locations are consistent.

For architects, it can compare a structural IFC exported from Revit, ETABS, or SAP2000 with an architectural IFC, helping quickly identify size or position differences between the architectural and structural models.

• Check whether Revit and analysis model member sizes are consistent before drawing production
• Coordinate architectural and structural models
• Check size and position offsets after model conversion
• Quickly identify which members changed during a project
• Reduce the time spent manually checking members one by one

The system mainly reads two core pieces of information for each member: section and axis.

The section represents member size, such as RECT-500x800, BOX-300x300x12, or H-400x200x8x13.

The axis can be understood as the centerline along the member length. After extracting the axis, the system uses it to evaluate position, angle, shape, and length, then combines that with section size to determine whether the two members are consistent.

The system reads the member section and uses the axis as the basis for position, angle, shape, and length checks.

During pairing, the system uses each member in Model A as a reference and searches nearby for possible corresponding members in Model B.

If the two model coordinate systems are not aligned, corresponding beams or columns may be too far apart, causing the system to miss the correct pairing.

Therefore, when the two model origins or coordinates differ significantly, it is recommended to align the models first. The system can then search for corresponding members within a reasonable range and proceed with comparison.

“Pairing” determines which member or members in Model B correspond to a member in Model A. Common pairing situations include:

• One member in Model A corresponds to one member in Model B
• One member in Model A corresponds to multiple members in Model B due to different modeling methods
• Multiple members in Model A correspond to one member in Model B due to different modeling methods
• A member exists only in Model A when no corresponding member is found
• A member exists only in Model B when no corresponding member is found

“Comparison” checks whether paired members have differences, such as position, angle, section, shape, or length differences.

Simply put, pairing finds “which members belong together,” while comparison checks “whether there are differences within the pair.”

After pairing, the system marks position, length, section, and other differences within the same member group.

Ideally, the system can directly read each member’s section size from the IFC data.

In real projects, some members may be affected by joins, cuts, end trimming, conversion, or software-specific IFC export methods, making it difficult to infer the original section from geometry alone.

For example, a rectangular beam may be cut by columns, walls, or other elements at its ends, so its geometric shape is no longer a clean rectangle. In this case, geometry alone may not be enough to identify the correct section.

Section naming rules are used when geometry-based section detection is insufficient. The member name can then be used to specify the section size.

For example:

• Map member name G50x80 to RECT-500x800
• Map member name BOX150 to BOX-150x150x12
• Map member name G402 to H-400x200x8x13

Automatic section naming detection: the system first attempts to find patterns in existing member names and apply possible section naming rules. Users can confirm, edit, or add rules to match project or company naming conventions.

Module rule: parse the section from size modules in the name
For example: G{B}x{H}.

Section name rule: map a specific name directly to a standard section
For example: H-148x100x6x9.

If the automatic result is not as expected, you can correct it based on the type of issue.

• If section parsing is incorrect, add or adjust section naming rules, or directly map a type of name to a section.
• If pairing is incorrect, use manual pairing, unpairing, or rerun local pairing.
• If some members should not be compared, add them to the ignore list.
• If the comparison is too strict or too loose, adjust comparison tolerances such as position, angle, length, or shape thresholds.

These features help the tool adapt to different company modeling habits, IFC export results from different software, and project-specific checking requirements.

Yes.

Users can adjust comparison items and certain tolerances based on project needs. For example, you can choose whether to compare position, angle, shape, section, or length, and adjust thresholds for position offset, angle difference, and length difference.

This is useful for different stages of model checking. In early coordination, you may only want to confirm the main beam and column sizes. Before drawing production, you may want stricter checks for position, angle, and length differences.

The system temporarily processes uploaded IFC files and comparison results in order to complete the model comparison workflow.

The system regularly clears uploaded data and generated results. Temporary data is generally removed within 24 hours.

If you choose to provide IFC files through the feedback form and describe the issue you encountered, it will greatly help improve section parsing, pairing accuracy, and compatibility with IFC exports from different software.