Hi @rufin
The below #share is a partial workflow that you may be able to adjust for your purposes. This has been adapted from my other scripting and will only update the Structural Framing if it occurs below the slab for a start. The workflow I mentioned earlier negates this limitation, so if you want to continue to develop your understanding perhaps you should keep going there. Hope this helps 
(D1.3) Framing to Underside of Floor.dyn (19.2 KB)
