Homes are currently designed and built with no expectation of home automation support. One reason for that is the old chicken-and-egg problem. Home-automation devices are designed with the assumption that homes provide only outlets, so homes are designed with the assumption that only outlets are required in order to support home automation devices.
I think all of that will change as smart-home appliances go more mainstream -- a process that's happening quickly.
Read more: http://www.computerworld.com/article/3053702/personal-technology/a-smart-home-thats-really-smart.html