Surface By Loft problem

I have been trying to create a surface by crossSections. When i try to make a surface with 2 nurbs curves, dynamo give " Warning: Surface.ByLoft operation failed.
Unable to compute edge from curve : IG_CURVE_SELF_INTERSECTS – Self-intersecting curve " error.

I had a work around with this. I divide this curves into points and created lines with these points. Then i created a surface with these secondary lines. So far so good, however when i imported this surface to revit, it does not create roof or wall with this created surface.

I think i have to modify or correct these main two nurbs lines in order to create a correct surface.

When i select this roof surface, it doent even recognize it as a face and gives a null.

Any ideas? Thank you

MT.rfa (812 KB)

Uploaded model

Not sure where your geometry originated, but it’s… off. Note that if you select either of the two curved edges that make up the curved sides of the import instance and wire that into a Curve.PointAtParameter node with parameter values 0…1…#100 and you’ll see there is something off… These parameters should be dispersed evenly, but they’re clumped up on the short side and the curve.

So, towards that end, I wrote a small Dynamo graph that should get you back up and running.


Dynamo 1.3.3 if that wasn’t clear.


Thank you Jacob, graph works like a charm!

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