to create your floor plan use the line tool. The line tool can be selecteed by clicking the pencil on the left side of the toolbar or by clicking "L".
Step 1: Raise the Walls
in order to create the walls youre going to first click "F" to select the off set tool. Now click and drag the outside of your floor plan to the thickness you want your walls to be. now to raise the flat outer trim to walls you have to select the "push and pull" tool by pressing "p" on your keyboard and click and drag the outer trim to the height you would like.
Step 2: Closing the Roof
Once you are happy with the shape and height of your house you can close the roof off by drawing a line across the roof. This should automaticly register it as a surface and cover your structure.
Step 3: Expanding the Roof Out
to expand your roof beyond the walls below it you are going to have to use the offset tool "F" to expand it out to a distant you are comfortable with. to remove the lines by using the select tool and deleting them by pressing the delete button on your keyboard.
Step 4: Thickening the Roof
Again we are using the push/pull tool to add thickness to the roof. (tip: press Ctrl to create a new object instead of just stretching the original one.)
Step 5: The Pitched Roof
in order to have a pitched roof you need to draw the design you want on the flat roof using the line tool. Once happy select the central line and use the move tool "M" to pull it up the blue axis in the background.
Step 6: Adding Doors and Windows
in order to add windows, doors, and many other details click the windows tab and select components. a box will drop down with your different options. if you want more models or different styles you can download them from the internet or design them yourself.