In class B airspace, the five mile radious from the iarport extends down to the surface. It then works outward, with the 30mile radius beginning at 10,000 feet. It's like an upside down tiered wedding cake. The rest, class "C" airspace is uncontrolled from the surface to 18,000 feet. Anything above 18,000 feet everywhere is controlled and comprises "J" Routes or class "A" airspace.
If you don't live within ten miles of a big city airport, you're ok.
Flying a drone over my home, to my way of thinking, unless it’s a kid’s toy and I’ve been warned about it by a considerate neighbor…is a prima facie hostile act. But I’d love for it to be close enough for a shotgun...