If you are looking for some extra room in your home, have you thought about finishing your attic? If so, you will find that it can be a very rewarding project, even though there are some hurdles along the way.
The main concern to keep in mind is that you might be dealing with a completely separate temperature zone in your attic. Often there will be insulation between the attic and your living space, and this leaves the attic at the mercy of the elements. Even if you were to insulate against the outside, you should still keep your attic on a separate system than the rest of your home to get better control.
Height might be an issue as well. For tall people, it might be hard to stand up straight in an attic, and you should remember that there will most likely be some space lost when you finish your attic, so even if you can stand up straight in the attic right now, this might not be the case after the work is finished.