On the modify panel on the ribbon, Revit offers three trim/extend keys: Trim/Extend to Corner, Trim/Extend Single Elements and Trim/Extend Multiple Elements. We will focus on Trim/Extend Multiple Elements functionality.
Prior to Revit 2015 if you wanted to trim back or extend several partition walls to a new boundary masonry wall for instance you had to select the trim/extend multiple tool, click on the boundary wall and then click on each individual wall in turn. This could be time consuming if you had several walls to trim or extend.
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