Extending a planear surface

Hello, I have been trying to find a way to extend the pleaner surface between the two hip roofs to create a roof saddle.

I tried adding a vertical plane surface at the centerpoint thinking I would have an intersection point to snap to, but it does not recognize the intersecting point.

Any suggestions would be greatly appreciated. Thank you

Hi Kevin - I’m not sure what shape you’re after - do you have a an example image or something that you can post?



Here is the top view of the 3d model.

Here is a 2d drawing of what I want it to do. I will circle the area of the problem.


Image this roof system. In the 3d model there is a horizontal valley between the two hip roofs where they connect. A portion of the top trapizoid of the lower right square building needs to extend left. A portion of the lower trapizoid of the large building needs to extend right to form a new roof ridge line between the two buildings and two valleys where the perpendicular planes meet.

I wonder if you run the intersect Command on the vertical plane and the 2 hip roofs . This would give you points to snap to , then build off these points. Hope that made sense. Or maybe I dont understand. —Mark

Yeah… the level line is where the lines from intersecting the pairs of planes from neighboring roof planes (one from each roof) intesect the existing edges on the roofs. once you have those points I guess you can make a new polyline and PlanarSrf it or use it to trim your reference planes.

RoofSaddle_Maybe.3dm (137.2 KB)


Thanks Pascal and Mark. I will try both methods tomorrow.