Wow, you're even more CV-crazy than I am. Now if that is safe? By almost no means.
In Reply To #3
I thought you meant you were going to have a tower just floating out, not a stairway from one house to another, that's not a problem. But if you put a stairway fromyour house and then had another small floating room, that's impossible, without steel supports. Still, if it weighs a lot less than the rest of your house, it should be possible.