Revit Change Analysis

How do you confidently determine the change(s) that has been applied to a newer version of a model using Revit? Yes, there is the "Compare Models" tool from the Revit Extensions add-in, but all this does is to produce a (very lengthy) list, that is not dynamically or visually linked to the model(s) being compared (Yes you can make use of the ElementID values to select them, but you have to exit the comparison results first, then open and run it again if you want to continue).

In the past, to ensure that I do not miss important model changes, I used to run the "Element Positioning" tool from the Revit Extensions, then generate schedules of important model category elements, such as Walls, Floors, Columns (Structural and Architectural), Structural Framing and some others. After generating the schedules, I would then export the schedules to CSV so that I can open them in Excel (This would be done for both versions / revisions of the model). Once I had the spreadsheets, I'd run a comparison between the "versioned" model elements, and highlight possible geometry, elevation & profile changes. This could then be added to a "Elements To Check" list for post-processing. I would apply this workflow to models received from others (Architects, MEP Engineers etc.), as well as on my own models, to ensure that I have a full understanding of what has changed between issued models.

Although the above mentioned workflow works very accurately, it is extremely time consuming (and very boring). I then decided it was time to automate this process. First I tried using visual model elements displays for change types (Green = New Elements, Red = Removed Elements, Grey = Unchanged Elements) in Navisworks, this worked well, but again required a lot of manual input. Finally I decided to develop an add-In for Revit that would manage all of this information for me automatically. I now simply have to select the current version of the model, an older version, specify a few settings and the program will generate a "spreadsheet-like" data representation of the model, accompanied by a visual result based on the model comparison results (via a template file that can be customised / extended).

The Add-In ribbon:

The required input:

The results:

Now I have a tool that completely automates a tried-and-tested model comparison workflow which dynamically links to model elements, and displays model changes visually in Revit. I call this process "Model Change Analysis", not sure if the term already exists or not, but it pretty much nails it. Currently, only Walls, Floors, Columns (Structural and Architectural) and Structural Framing is available for comparison analysis, but more element categories to come soon.

This application is now available on the Autodesk Exchange Store, have a look:

Here is a YouTube demo video:

I hope you find this as useful as I have.

Regards,

Chris