For example, if the top of your wall is 6 feet above the bottom plane, the wall will be “cut” at the cut plane, but if the top is less than 6 feet, the entire wall will be displayed with projection lines. Walls shorter than 6 feet (2 meters) are not cut, even when they are intersected by the cut plane.There are two reasons that this would happen:

In some cases, elements that are intersected by the cut plane will be displayed using the projection line weight rather than the cut line weight. These elements are displayed using the projection line weight when they are above the cut plane. Elements above the cut plane are not displayed unless their categories are window, casework or general models. Elements below the cut plane will be displayed with the projection line weight, and elements that the cut plane intersects with will be displayed with the cut line weight. The element used to display objects is determined by the height of the cut plane. Each element that is within the view range is displayed using the cut line weight, projection line weight, or the line style. If you need to work around this to have certain elements outside the View Range visible in your view, you can set an underlay to display a level outside the View Range. Generally, elements outside the view range do not display. Now that we’ve defined the View Range, let’s discuss how it affects the visibility of elements in the view.

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