Using the Trim Tool with Architectural Objects

The Trim tool can be used to trim Roof Slabs, and Walls with closed 2D objects.
The 2D object must be on the same workplane as the 3D entity to be trimmed. Use Workplane by Entity to set the correct workplane before drawing the trimming object. Since the workplane for walls is horizontal not vertical the effects of the trim are more limited.
To Trim an architectural object with the Trim tool:

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