If it is a slab you can do alot more than the floor boxes. You can stub up for all the recepts on the main floor. Saves on materials. Do you require a foundation bonding grid? I think it may be required but not sure. You do have a licensed electrical contractor on this right?If this is a slab, you'll need conduit for the kitchen island and any floor box receps.
Is that a question? Because I was just going to ask.Foundation bonding grid = UFER ground
Is that a question? Because I was just going to ask.
From what I can see and understand in my quick internet research into what a Ufer ground is, I can see that A) it's required in a few jurisdictions, particularly where soil conductivity tends to be poor, B) generally a good idea anyhow, and C) despite the above, still fairly rare in residential construction.
What about the labor and materials combined. I think you would work less and spend less if you put as much as possible in the slab. Future work will also be much easier. He only has one opportunity. Just the way I would do it.I am pretty sure romex is less expensive to install than pipe and wire.