Preparation of Amendment BIM e-Submission with Autodesk Design Review Compare Tool

In Singapore CAD Standard, “SS CP 83: Part 5” aims for visual checking by using colours. That aspect of visual checking is perhaps most important for submissions to authorities where certain colours have been specified for “proposed”, “existing” and “deleted” elements.

In BIM, Revit phase filtering process for A&A took a lot of time since that phases are applied to elements and controlled by views. For instance, in a residential project with several types of unit, after you did 3 colours changing in a typical unit group, it cannot update the rest of the similar groups in the Revit files. To gain the productivity by saving man hours, keeping smaller native file size (especially Revit) and avoiding creation of extra building objects (elements), alternatively we can use Autodesk Design Review to compare the original sheet to the revised sheet to identify differences in the geometry of building objects or elements by colors in accordance with SS CP83 Part 5 for projects previously done and approved with BIM submission and to re-submit the changes as amendment BIM submission.

Design Review can be used to compare differences in vector content (geometry) between two 2D sheets in separate DWF files that have the same sheet size and unit settings.

I am going to show you how to compare design changes with Design Review. First of all, open your approved DWF in Design Review, and select a sheet that you want to compare.

(Above figure shows a DWF Approved Floor Plan sheet: Elements in Cyan colors can be re-exported from Revit by overriding Phases Filters.)

Go to Tools menu, and then from Canvas tab, click Compare Sheets. The compare dialog box will open.

From the compare dialog box, click Options. The Compare Options dialog box will open. 
                                                         

Now you can change the default colors to the required Magenta and Yellow in accordance with SS CP83 Part 5. Click OK to go back to the compare dialog box.                                                          

   

From the compare dialog box, click Browse. Navigate to the folder to find the updated DWF file of the same drawing set, created at a different time and then select the sheet you wish to compare to the sheet currently in the canvas.  

Final result is essentially an automatic markup of the DWF sheet showing what are the proposed elements(NEW) in Magenta and what have been deleted(DEMOLISHED) in Yellow.  

               

Any changes between the 2D sheets are identified as separate markups, one for Additions and one for Deletions, in the open DWF file. The Additions markup identifies the geometry that would need to be added to the original sheet to make it match the second sheet. The Deletions markup identifies the geometry that would need to be deleted from the original sheet to make it match the second sheet.

Most of the time, contractor will receive a new version of a DWF file, but changes were not identified by the architect. The contractor can use Design Review to compare the original sheet to the revised sheet to identify differences in the geometry, including changes in polyline attributes such as line pattern or line weight.

Doing this electronically with a process that identifies additions and deletions goes beyond what we traditionally done by aligning and eyeballing sheets of paper or overlapping two CAD drawings and finding changes.

Occasionally, comparing DWF files may produce some unexpected results. Since DWF is a published file format, DWF files are susceptible to the output eccentricities of publishing programs.

Be aware that Design Review will identify all geometric differences between two DWF files, whether the difference is made intentionally by a designer or unintentionally by an anomaly in a publishing program.

I hope this process will improve over time with future releases of Autodesk Design Review.