01: The first thing I did was set a house blue print as the background in my blender window. This is so I can use it as a blue print of the house so i can 'trace' the layout of the house. Next I added a plane and scaled it so it fits the floor of the house in the background image.
02: I then started to subdivide the floor several times. I did this by adding subdivisions where the walls etc will go. Once finished I went into edit mode and deleted some of the subdivisions so there is room for the floors and doors in the house. Once I was happy where the walls are I then started to extrude the walls which makes a basic layout in the house.
03: I started to delete some faces on the outside of the building to make room for the outside windows and the doors. To create the window and door frames frames I duplicated the inside of the windows and the doors and then extruded and sub divide the window frame until I was satisfied with the results. Once I happy I placed it back into the window frame and the doors back into the door frame.
Here is the final model (with roof & without roof.)
