The next drawing tool that I'll show you is the Draw Wall tool. Drawing walls simply a matter of dragging your finger from where you wish the wall to start, to where you want it to end. An entire floor plan can be drawn by simply adding one wall after another. Let me show you by drawing a wall extending out from one of the sides of this room.
https://itunes.apple.com/us/app/floorplans/id445305220?mt=8