Typically consisting of a combination of high-tech Category 5 wiring and coaxial cable, so-called "structured" or advanced wiring schemes allow homeowners to customize their use of technology to meet their individual needs. According to the National Association of Home Builders, 34 percent of homebuilders now offer structured wiring packages as standard or optional amenities. Fiber-optic cable is also available, but its installation is more difficult and expensive. (Bill Gates's $30-million Seattle home reportedly has miles of fiber-optic cable. Guests receive computer chips on entering that control lights, temperature and other settings as they move through the sprawling complex.)

When plans for a new luxury home include structured wiring, many different built-in home automation technologies become possible.

The gamut runs from a fairly simple security system that will alert you via your computer at work should something be amiss back at home, to complete home-automation systems that seamlessly integrate home-entertainment systems, indoor and outdoor lighting, appliances, lawn sprinkler systems, climate control systems and Internet access points.