You can use both the Clip Surface command and the Clip tool to clip holes in a roof object.
To set the type of hole cut (vertical, splayed, or square), edit the roof as described in Changing the Roof Edge Shape.
To create a cutout with the Clip Surface command:
Draw one or more 2D cutout shapes (rectangle, circle, oval, polygon, polyline, or arc) on the roof object.
Select the cutout object and the roof object.
Select Modify > Clip Surface.
The shapes are cut out of the roof, and the clip objects are selected.
Delete the clip objects.
To create a cutout with the Clip tool:
Select the roof object.
Click the Clip tool from the Basic palette.
Click Exclusion mode from the Tool bar, and then select the appropriate clipping shape (rectangle, polygon, or circle).
Click and drag to create a marquee box. The roof is clipped as defined by the clipping shape.
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