By John Flanagan
Introduction
Use the Split Face Tool to divide the face of an element (such as a wall or a floor) into regions for the application of different materials. After splitting the face, you can use the Paint tool to apply a different material to this section of face.
To split a face
Click Modify tabGeometry panel (Split Face).
Place the cursor on the element face to highlight it. You may need to press Tab to select the desired face.
Click to select the face.
Sketch the face area to split (in the example above the rectangle tool has been used).
Note: The sketch must be in a closed loop inside the face or an open loop that ends on the boundary of the face.
Click (Finish Edit Mode).
Tip: You can split the face of a column. However, if you plan to have multiple instances of the split-face column in your project, create the column in the Family Editor and apply the split there.
Conclusion
The Split Face tool splits the selected face of the element; it does not change the structure of the element. The Paint tool applies a material to the selected face of the element or family; it does not change the structure of the element.