When I did something like this in my Breezehome I use TCL to alow me to walk to where I needed the part and in the console Player.PlaceAtMe <partID> 1 then walked away to where I gould see and used the sePos x, y, z to place it took me about 3 or 4 hours,. you need to be aware also that some area's have subspaces in and around there so if you build into those you will see and empty space in game, do you not have this thread http://www.thenexusforums.com/index.php?/topic/477049-renovate-your-house-with-console/page__st__730 its long but it w wealth of info whats the part id for the floor or room or whatever you used in the command "Player.PlaceAtMe <partID> 1"