Add a Hole by Lines
You can add a hole to a horizontal structure. The hole can go through the entire structure or it can be added only to the selected structural layer. The same hole can cut several horizontal structures located side by side.
- Select a structure and a layer, if necessary.
- Select Plane Structure | Volume |  Hole Hole   Hole Using Lines. Hole Using Lines.
- In the case of a sloping structure, select, if the points are to be buildinged to the top
        or bottom surface of the structure. Measure height to
              top - The edge points are buildinged to the top surface of the
            structure. Measure height to
              top - The edge points are buildinged to the top surface of the
            structure.
 Measure height to
              bottom - The edge points are buildinged to the bottom surface of the
            structure. Measure height to
              bottom - The edge points are buildinged to the bottom surface of the
            structure.
 
- In the case of a sloping structure, select perpendicular or vertical edges to the hole. Perpendicular
              edge - The edge direction is perpendicular to the structure. Perpendicular
              edge - The edge direction is perpendicular to the structure.
 Vertical
              edge - The edges are vertical. Vertical
              edge - The edges are vertical.
 
- Select lines or a line chain. The lines can be single lines or they can form a closed polyline. The edge lines can reach outside the structure and run across several horizontal structures.
- Select Confirm.
Note: 
    
  - You can delete a hole from the structure by deleting its edge points.

