A cutting plane in a floor plan is a theoretical horizontal plane that slices through a building to create the floor plan view. It determines which elements of the building are visible and how they are represented.
Understanding the Floor Plan Cut Plane
The floor plan cut plane is a crucial element in architectural design and drafting. It establishes a consistent level at which the building is "cut" so that elements above the plane are generally not shown, and elements intersected by or below the plane are visible. Think of it like slicing a cake horizontally; you see the internal layers and the bottom of the cake, but not the top.
Key Aspects
- Horizontal Slice: The cutting plane is always horizontal.
- Elevation: Its elevation is adjustable in software to control what is shown. Typically, it's set around 4 feet (1.2 meters) above the floor level, but this can vary depending on the design and what the architect wants to emphasize.
- Visibility: Elements intersected by the cutting plane (like walls, columns) are shown in a cut representation, usually with a thicker line weight or a filled pattern. Elements below the plane (like fixtures, furniture) are shown as they appear from above. Elements above the plane are usually not shown unless specifically overridden (e.g., displaying upper cabinets or a mezzanine).
- Software Implementation: In Building Information Modeling (BIM) software such as Revit or ArchiCAD, the cutting plane is a parameter that can be adjusted globally for the entire view or overridden for specific elements.
How it Works
- Establish the Plane: The designer defines the height of the cutting plane.
- Intersection: The software identifies elements intersected by this plane.
- Representation: These intersected elements are displayed with a cut representation, emphasizing their location.
- Elements Below: Objects below the plane are shown from a top-down perspective, representing furniture, fixtures, and other floor-level details.
- Elements Above: Objects above the cut plane are generally hidden unless the software or view settings are configured to display them (e.g., dashed lines indicating overhead beams).
Impact on Floor Plan Interpretation
The location of the cutting plane significantly affects how the floor plan is interpreted. A higher cutting plane might show elements like windowsills, while a lower one might obscure them.
Example
Consider a typical wall with a window. If the cutting plane is set above the window sill, the floor plan will show the wall cut through its solid section. The window itself will be visible as an opening in the wall. Furniture placed along the wall will also be visible below the cutting plane.
