Most of this could be achieved with the wall family directly by using layers for the core and faces and applying a hatch in the Materials.
As regards the reinforcement element this would be very difficult to do especially if it is needed to to stretch and still meet dimensional constraints.
I think a line based family would be more appropriate here which could stretch and keep elements spaced and aligned but a lot more work involved.
in all honesty I would just model the reinforcement in the wall not only will it show in plan but also in sections and elevations and can be tagged and scheduled and would only take a few minutes to achieve.
Jay Colcombe
Autodesk Certified Instructor
Revit Architecture & Structure Certified Professional
AutoCAD Certified Professional
B.Sc. Hons Civil & Structural Engineering
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