Hi Artur
In general any vertical panel can be 'extended' to a new level but I'm not sure if I understand this particular design situation correctly.
I mean:
stroxy wrote in the first message:
I have a recatangular panel, representing a raft foundation. I want to modify the area under the lift (elevator) core walls by dropping it deeper (to accomodate lift equipment) , what is the best workflow to achieve that,short of remodelling the whole panel from scratch?
I suggest that Instead of
3a. Create vertical panels to connect edges of the opening with edges of the newly created panel
you can write:
3a. extend the lift (elevator) core walls to edges of the newly created panel.
Isn't it better to extend the lift core walls rather than creating vertical panel to conncet edges of the opening with edges of the newly created panel?