Model Comparison in SMC v9.8

NOTE: The following article contains much of the same content as in the articles Model Comparison – Sol/206 and New in SMC v9.7.15 Model Comparison Improvements but is updated with screenshots of the new interface of Solibri Model Checker (SMC) v9.8. If you are running an earlier version of SMC, please refer to the previously published article(s).



Solibri Model Checker (SMC) has a very powerful rule template named Model Comparison (Rule Template # SOL/206) that is able to compare two versions of an IFC model for differences. This rule template is used in the Model Revisions Comparison – Architecture ruleset found in the Architectural folder of the rulesets included with SMC.

You are able to find information for this rule in the help topics by following the link below to the Solibri Solution Center:

The following article will provide an additional explanation using the Model Revisions Comparison – Architecture ruleset and two versions of the SMC Building sample models that come with SMC.

First, open SMC v9.8 and set your role to BIM Validation – Architectural by clicking File > Roles > Open. By using this role, when you click the Add Rulesets button in the Checking View, the Model Revisions Comparison – Architectural ruleset will be listed in the dialog box that opens, with the default rulesets included in this role.


NOTE: The Model Revisions Comparison – Architectural ruleset will not be loaded automatically when you open an IFC since it is not “Starred.”  If you wish to have the ruleset automatically open in the Checking view, you must “Star” its listing in the Roles window and resave the role (see above).

Now that your role is set, click File > Open Model… and open SMC Building.ifc and SMC Building – modified.ifc found in the Samples\IFC folder. After the IFC models load, leave the Ensure Model Disciplines dialog as it is with both models set to Architectural and click the OK button.

NOTE: The Model Comparison rule template is for comparing IFC models, not SMC models. Solibri Model Checker is unable to load multiple .smc files at the same time.

With the two versions of the same IFC model loaded, you can now open the Model Revisions Comparison – Architecture ruleset.  Select the Checking layout tab at the top of the SMC window, and you’ll notice that the BIM Validation – ArchitecturalGeneral Space Check, and Intersections Between Architectural Components rulesets have already loaded by default using the role you previously selected. If the To-Do dialog opens, you can simply click the X button in the top right corner, as you won’t need to verify any of these tasks to ensure the results are accurate.

Click the OPEN_RULESET_FOR_EDITING Add Rulesets button to add the Model Revisions Comparison – Architectural ruleset.


If you want, you can right-click the other three rulesets listed in the Checking view and select Disable to save time by not running those checks.

Click the Check button in the Checking view and select the Component Comparison rule under the Model Revision Comparison – Architectural ruleset to view its results in the Results view. You may notice a result stating Incorrect Model Timestamps (see below), warning that the Old Model set in the Rule Parameters does not have an earlier Timestamp than the New Model. This is due to the modified IFC being saved prior to the original model. It is important to point this out since with the Old Model and New Model set incorrectly, the rule will incorrectly report components as being added that were actually removed and vice versa.


You can ignore the Incorrect Model Timestamps issue as it is a non-issue

To view the rule’s parameters right-click the rule in the Checking view and select Rule Parameters.  At the top of the Parameters Dialog Bow (see below) you’ll find drop-down boxes for the Old Model and New Model. Set the Old Model drop-down box to SMC Building and the New Model drop-down box to SMC Building – modified (see below).

Notice next to the drop-down boxes, you can set the colors for the Old Model and New Model. By default, the Old Model is set to a red color with 60% transparency and the New Model is set to a blue color with 60% transparency. Therefore, if a component was removed, it will show up as Red, since it only existed in the Old Model. If a component is added, it will show up as blue as it only exists in the New Model. If a component is modified, it exists in both the Old Model and New Model. If the modified component moved to a new location, you’ll see the component in two different locations: one as red and one as blue. However, if only a property was modified for a component, the component will reside in the same location in both the Old Model and New Model, in purple, caused by the overlapping colors of the components.

Below the old and new model drop-down boxes is a checkbox labeled “Identify components only with GUID.”  When marked, SMC ignores the geometry of a component in determining if it was added/removed in the model and relies only on the GUID of the component. For example, if you delete a component in the design application and replace it with a new component, the GUID of the new component will differ from that in the old model.  With the checkbox marked, there will be an “Added” result for the component in the new model and a “Removed” result for the component in the old model.  However, if you leave the checkbox unmarked, SMC will return a “Modified” result for the component stating what has changed (e.g. Geometry, Type, etc.)

Next, you’ll notice under Checked Components, we are checking Any components from an Architectural Model, but Excluding Openings and Spaces. These are excluded since spaces will be checked on their own in the Space Comparison rule and openings are normally created by doors or windows, which will already be compared.

NOTE: By setting the Component column under Checked Components to Any, only components that have geometry will be checked. This doesn’t include container components such as Buildings, Floors, Systems, etc. If you wish to compare container components, you’ll have to add a row to the filter to Include those individual container components as well.

Below the Checked components, is a checkbox labeled “Geometries”. When marked, a result is returned for any component that has had its actual geometry (what you see in the 3D View) modified.

Below that checkbox is the “Compared Properties” list.  Here you can add any property you wish to compare across versions of a model. To add a property, click the ADD_ROW Insert Property button.  A dialog window will open and allow you to select from a one of the property groups.


Lastly, Model Comparison is one of the rule templates in SMC that has a configurable report. The Report section of the Parameters dialog (see above) allows a user to customize what columns are included in the report. The table on the left allows a user to specify which classifying columns to report and their order. These are the left-most columns of the report that will sort the components in the report by their column values. The table on the right in the Report section of the Parameters dialog (see above) allows a user to specify what components and which of their quantity and location properties to report. For example, in the report of this rule, components will first be grouped and sorted by the floor they are located on, then by the component (Door, Wall, etc) they are, and then by their Type. You’ll also notice that Roofs, Slabs, Walls, and Suspended Ceilings will have their Areas reported, though not their Lengths. Only Beams and Columns will have their Lengths reported, but not their Areas.

Set the Old Model and New Model drop-down boxes to SMC Building and SMC Building – modified respectively in the Rule Parameters of the Space Comparison rule in the Checking view as you did for the Component Comparison rule.  Now that the Rule Parameters are better understood and correctly set, click Check in the Checking view to re-run the check.

In the Results view, notice there are three categories of results listed: AddedRemoved, and Modified. Double-click and expand the Added category to zoom to the components that were added in the modified model.


You’ll see that a door, a suspended ceiling, and a wall have been added to the modified model. Again, as these are components that only exist in the New Model, they show in the 3D view as blue.

In the Results view, if you expand the Modified category, scroll to and double-click the result “Wall.0.16 – Wall.0.17,” you’ll see that one of the walls in the New Model was moved and had an opening cut out of it for the door that was added:


You can see that it moved in the 3D view as it is shown in two locations: in red from the Old Model, and in blue from the New Model. Notice the sub-category states “Wall: Geometry, Location, Quantity”.  The results are organized first by what the component is that has changed and then by what has changed about that component.  The Geometry has changed since an opening was cut out of the geometry of the wall for the door that was added. The Location properties have changed since the wall itself has shifted locations. The Quantity properties have changed since the area of the wall is now smaller due to the opening that was cut out of it.

Also notice that when you select the result in the Results view, you see a detailed listing in the Info view of all the properties and their values that have changed.

In the Results view, expand the Removed category until you find the “Double Sash Window 16” result of a window that was removed from the model.  You can see that the window was removed in the modified model as the window only appears red in one location (where the modified wall was later moved to) from the Old Model.


Double-click the REPORT_BUTTON Report icon in the Checking view to open the report of the results of the Component Comparison rule.


You’ll see changes that have been made to components, which are sorted first by the floor that they are located on, then by what component they are, and then by their Type.


For example, when viewing this report we see that 2 Door components of Type Door 16 have been added to the Ground floor level in the modified model.  We can also see that 15.07 sq ft of Wall of Type EW-3 100 have been removed from the Roof level in the modified model; however, 36.06 sq ft of Slab of Type FS-2 200 has been added.

Model Comparison in SMC v9.8

New in SMC v9.7.15: Model Comparison Improvements

In the latest version of Solibri Model Checker (SMC) v9.7.15, enhancements have been made to the Model Comparison (SOL/206) rule template. The rule now allows you to check if components have been added or removed based on their Global Unique ID (GUID) rather than only their geometry as in the previous version. Also, you now have the ability to compare specific individual properties from the Identifications, Location, and Quantities property groups instead of those property groups in their entirety. Both of these improvements allow for a more precise check for changes that have occurred in iterations of a building information model.

The remainder of this article will explain these enhancements in further detail. For an overview of the Model Comparison rule prior to these enhancements, please see the article:

Identify Components Only With GUID

Version 9.7.15 of SMC adds an “Identify components only with GUID” checkbox. When marked, SMC ignores the geometry of a component in determining if it still exists in the model.

In the example below, two versions of the same model are loaded that contain a door attached to a wall.

The door in the old version of the model is of type 36″ X 84″ and the value of its GUID is 1iZj__xXf78BSFTMaX7Drh.

This model was later modified by deleting the door and replacing it with a new door of type 30″ X 80″ that has been moved 6″.  Since the door was deleted and replaced rather than modified in Revit, the GUID has changed to 1hm2STqeTCcuuYSoDEhuFt.

With “Identify components only by GUID” unmarked in the Model Comparison rule check, the Results view lists the door as being modified with its various changes to geometry, identification, and location in the Info view.  Since the two versions of the doors are at the same relative location, it is treated as the same door that was modified even though it was actually removed, then added back in Revit. 

However, with the “Identify components only by GUID” checkbox marked, the results will then list the door from the old model as removed, while the door in the new model was added rather than stating the door was modified.  The old door appears red in the 3D view, while the new door appears blue.  Interestingly, the wall will remain modified as the opening that the door cutout is smaller and shifted.

Note, if you were to simply change the location and type of the door in Revit without removing and replacing it, the results would state that the door was modified rather than removed and added with the “Identify components only by GUID” checkbox marked.  This is because you modified the door in Revit, which does not change the GUID.

The previous version of SMC didn’t have the option to identify components only by GUID and always performed the check as if the checkbox is unmarked in the example above.

Compare Property List

In the previous version of SMC, the Model Comparison rule was limited to check boxes of property groups that checked all properties that fell under the categories of those property groups.

In the screenshot of SMC v9.6, two slabs have various quantities changed. You can see in the 3D view that the length was increased along the x-axis.

In the Rule Parameters view of the version of the rule template in version 9.6, only the quantities checkbox is marked.  SMC will thereby check for any changes to any property that falls under that category.

However, you may only be interested in a particular property, such as area, and only wish to have that listed in the Info view to copy into your issue slide. If the area of a slab changes, logically, so will the gross area, perimeter, and volume of the slab, which is why they are reported as well.

In the screenshot of the Rule Parameters view in new SMC version 9.7.15 below, you see the compare rule that had the checkbox for quantities marked.  The Compared Properties list contains the long listing of all those properties from the Quantities property group.

We can select those properties and click the Remove Row  button.  Then click the Add Row  button to add only the Area property.  Below, you can see that you can select any individual property from one of the property groups.

We set our rule to check for changes for the areas of components.

The Results and Info view now only show the change in the area of components.

New in SMC v9.7.15: Model Comparison Improvements

Enhanced and Advanced Model Comparison, using the Checked Components View

The purpose of this article is to explain and explore how the Checked Components feature in Solibri Model Checker (SMC) significantly extends the benefits of a typical Model Comparison check.  Comparing models is a basic, yet important capability within SMC. It allows you to load two different versions of a BIM file, then compare them to identify where any differences have occurred.  The results clearly articulate the changes that have been made, both in the geometry (objects) and the associated properties (data). This is presented as components that have been added, removed, or modified.  By using the Checked Components view, you can also see which components remain unchanged, which verifies that all the components have been checked.

You can find more information about how to use the Model Comparison rule by reading several articles written on the topic at:

If you would like additional information about the Checked Components view,  please follow the link below:

When running the model comparison rule in SMC, the results you would expect to see in the Checking Results window include:

Added: Components that have been added since the previous model was submitted (shown in the newest model)

Removed: Components removed from the previous model

Modified: Components that still remain in the newer model, but have changed, in any way, from their original form

What would not be seen in the Checking Results are all other components that were not added, removed, or modified.  For example, if there is an expectation that a space footprint would have changed in the new version of the model and that change is not showing up in the Checking Results, you can look at the Checked Components view to verify that the room was actually checked by the model comparison rule, and whether there was in fact a change to the space.

There may be several reasons that the example space change is not showing up in the results.  Perhaps the model comparison check is not checking geometry changes.  Or there may be an exemption that specifies not to check spaces.  Or, the space was checked and there was in fact no change to the space.  It is important to be able to determine which of these is the actual reason.

In the Checked Components window, the ‘Failed’ items from each model are listed by default.


By selecting the dropdown next to ‘Show Failed’ other visualization options appear.  ‘Show All Checked’ lists the components that have been checked using the rule.  If all components in the model are listed, that means all components will have been run through the model comparison.  By selecting ‘Show All Checked,’ the 3D window will display the checked components.


You can then navigate through the model to verify that the space or component in question is displayed.  If it is not, then it is not one of the components that were checked.  As mentioned before, this could be due to an exemption of this space in the rule parameters, and can be addressed by correcting the rule parameters to include such space changes.

If it is shown as checked, you can then return to the Checked Components window and select ‘Show Passed’ to verify that it did in fact ‘Pass’ the model comparison check, and therefore was unchanged.


If it still appears in the 3D window while in the ‘Show Passed’ mode, the space was not changed between versions.

It is important to recognize that there are many different parameters that can affect the way a model is compared in SMC.  A user can limit their comparisons to specific types of components and their geometry, or broadly check an entire model for any changes of any kind.  Using the Checked Components view in conjunction with the Model Comparison rule provides greater insight into the details of the results, and should give you much greater confidence in the Quality of the model, as well.

Enhanced and Advanced Model Comparison, using the Checked Components View

Setting up your basic Model Comparison Check

To conduct a quick model comparison in Solibri Model Checker (without customization), use the ruleset titled “Model Revisions Comparison.” Solibri Model Checker contains 3 version of this ruleset, one for Architectural, one for Structural, and one for MEP models.

To get started, a user must load two versions of the same IFC model, for example, the previous version first, and then the current version.  Do so by loading the previous IFC, and then “Add File” from the File tab to load the current IFC concurrently with the first.


Once both IFCs are loaded, go to the Checking tab.  Here, a window will appear asking which ruleset to use for this check.  Select “Model Revisions Comparison,” then select the “Check” button to run the comparison.


The results of this check are broken into two categories: Components and Spaces.  If there have been changes to the Components in a model, those changes will be listed under the Components rule.  If spaces have been changed, they will be under the Spaces rule.


Select the Component Comparison rule, and the Results window will display Added, Removed, and Modified components.


These results are displayed in real-time in the 3D window/model, and can be reviewed and then saved as a presentation.

Setting up your basic Model Comparison Check

Finding Precise Changes via Model Comparison

The previous article MODEL COMPARISON – SOL/206 provides a detailed introductory explanation on how to compare two versions of a model.  In this article, we focus on tips to partition model comparison checks into more granular pieces, namely results of what components have been added/removed and how they have been modified in terms of their identifiers, quantities, locations, and property sets.

You can follow along with this article using the example file available through the link below:

SMC Building – Model Comparisons.smc

The example linked above was modified using the same IFC files and ruleset from the previous “MODEL COMPARISON – SOL/206” article. The image below shows which rules have been added based on the specific type of comparison to be checked:

Modified Model Revisions Comparison Ruleset
Modified Model Revisions Comparison Ruleset

After running the check for the “Component Comparison” rule, then expanding those results, you’ll find Added and Removed components listed first as a category of results:

Component Comparison - Added/Removed Results
Component Comparison – Added/Removed Results

These Added and Removed results will always be listed if found, and if running checks for other properties, they are listed first before the category of what has been modified.  If you wish to only see what components have been added/removed, you can simply uncheck all Compare checkboxes in Rule Parameters of the Model Comparison rule.  You can see below in the rule parameters of Component Comparison – Only Added/Removed, all checkboxes have been unmarked and the results of the check no longer list any components that have been modified.

Component Comparison - Only Added/Removed
Component Comparison – Only Added/Removed

Next, we’ll look at the Modified results category and the Identifications checkbox parameter of the Model Comparison rule.

In the Results view, after selecting the “Component Comparison” rule, you’ll notice results with “Reported Property” listed last in the sub-category:

Component Comparison - Identification Results
Component Comparison – Identification Results

If you expand the result category “Door: Geometry, Location, Quantity, Reported Property [0/1]”, and select the result “(OLD) Door.0.11 – (NEW) Door.12”, you’ll see a listing of changes to the component in the Info view:

Component Comparison - Door Results and Info Views
Component Comparison – Door Results and Info Views

The last two listings in the Info view (highlighted in the image above) are properties from the Identification category, which was marked in the rule parameters. These Identification properties are the same as the properties listed in the Identification tab of the Info view after selecting a component. In this result, the single swing door in the old file was swapped out for a double door in the new file. This explains why the Type and Operation parameters are listed as being changed.  The other listings of changes pertain to the geometry, quantity properties, and location properties.  If you are only interested in the changes of Identification properties, you can leave only that checkbox marked in the rule parameters of the Model Comparison rule.

Component Comparison - Identification Results and Info View
Component Comparison – Identification – Results and Info View

Notice there are fewer results listed in the Results view to review and the information regarding the change to the door only pertains to identification properties.

Notice again that the Added and Removed categories are still listed in the Results view.  The Compare checkboxes in the rule parameter only determine what will be listed under the Modified category.  If a component is added or removed in the model, it will always be listed regardless of what checkboxes are marked.

When the geometry of a component has changed, it will likely cause a change in the location properties and quantity properties of the component as well.  Notice in the image titled “Component Comparison – Door Results and Info Views”, that the Global X property has changed.  Since the double door is now larger, its Global X location property has shifted along the wall.  Also, its Area, Width, and Frame Length quantity properties are larger as well.

The Location of an object can change without its geometry changing by simply moving it. In the image below, you can see the four sinks in the model were raised by 20 mm, though their geometry remains the same:

Component Comparison - Location Results and Info View
Component Comparison – Location Results and Info View

Lastly, you may wish to only monitor changes in a specific property or set of properties.  For example, many IFC components such as doors and walls have common properties such as Fire Rating.  These are found under a property set named Pset_DoorCommon and Pset_WallCommon respectively.

In the rule PSET Common Properties Comparison, the rule parameters have the Property Sets check box marked and the table is populated with all of the various common property sets in the Property Set Name column.  The Property Name column contains an asterisk to denote that any property found under the property set is to be checked for changes.

PSET Common Properties Comparision
PSET Common Properties Comparison

In the Results view, we see that the Pset_SpaceCommon.GrossPlannedArea property has changed of a space.

PSET Common Properties Comparision - Results and Info View
PSET Common Properties Comparision – Results and Info View

You can create a Model Comparison rule to check for changes of properties of a specific use for the model. In the screenshot below, the property sets table is populated to check only those properties that pertain to COBie information for changes :

Checking Property Sets for COBie Information
Checking Property Sets for COBie Information

More information on COBie and SMC can be found through the link below:


Finding Precise Changes via Model Comparison