W-W-W What!? We are talking single family, indoor living spaces right? At that size they no longer qualify as "homes" they are complexes or estates! I hardly think the largest home in America, at 175,000 sq ft.- The Biltmore Estate -would be considered a "home". It is used as a hotel.
After 20,000 sq ft (A very large home) all standard methods of wiring have to be reconsidered entirely as an almost commercial or even industrial application.