Splitting a Toposurface

You can split a toposurface into 2 distinct surfaces and then edit those surfaces independently. To split a toposurface into more than 2 surfaces, use the Split Surface tool multiple times, further subdividing each piece of the toposurface as needed.

After splitting a surface, you can assign different materials to these surfaces to depict roads, lakes, plazas, or hills. You can also delete entire portions of the toposurface.

You can use the Split Surface tool to remove unwanted portions of a toposurface generated by an imported file, when the imported file fills unsurveyed areas with unwanted artifacts.

Note: If the Phase Demolished property of the toposurface is set to a value other than None and you then split the toposurface, this value is change to None for one of the resulting surfaces.

To split a toposurface

1. Open a site plan or 3D view.
2. Click Massing & Site tabModify Site panel (Split Surface).
3. In the drawing area, select the toposurface to split.

   Revit enters sketch mode.

4. Sketch the split surface.

   How to

   1. Click Modify | Split Surface tabDraw panel (Pick Lines), or use other sketch tools to split the toposurface.

      You cannot pick toposurface lines with the Pick Lines tool. You can pick other valid lines, such as walls.

   2. Sketch a single closed loop that does not touch boundaries of the surface, or sketch a single open loop. Both ends of an open loop must lay on the boundary of the surface. No part of the open loop can intersect or be coincident with the boundary of the surface.
   3. Click (Finish Edit Mode).

Example

Sample split surface