Hi there,
I think the error lies in the workflow you're using ( not bad, but it follows a different logic, the logic of free form modeling)
Try a different approach:
Keep the slab for you slab/floor up to the limits of the Envelope, then create a separate element for the Roof.
The second element - the roof - can then be done with a single Morph by "morphing" your existing roof ( so you don't loose what you already did )
If you are in a higher level of detail, then you should consider modeling it closer to what construction would be, maybe one roof for the top geometry and a slab for the soffit / ceiling?
In this way you don't have to "draft it" it will be all done with native AC elements, and the Plan representation will be correct.
Hope this helps
Nando Mogollon
Director @ BuilDigital
nando@buildigital.com.au
Using, Archicad Latest AU and INT. Revit Latest (have to keep comparing notes)
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