When I'm in my house by myself (which is usually during the work week), I'll work in different places around the house. (For much of what I do, a laptop is all I really need.) However, I do have a dedicated office with a door and, if other people are present it makes a huge difference in terms of distraction. I suppose I could adjust to an "open office plan" at home but having a dedicated (though not just dedicated to work) office is very useful.