creating a 2 story size wall
 

Hi there all,
I have a question pertaining to when creating a wall that extends to the second story of the house. Though first let me explain how I did it.

What I did was I first created the outer walls of a house that I am designing. Then I had started with building the first level floor and then on to the second level floor.

Now the problem I am having is that some of the walls of my house have areas where you can see the second floor. So another words some of the walls extend to the ceiling of the first floor which is the standard 8 feet and other walls extend to the ceiling of the second floor which is 16 feet plus the 10 3/4 inches for the spacing between the first and second floor. However, when this happens the second level 8 foot wall doesn't line-up perfectly with the first level 8 foot wall which makes it look like there is a seem in the 2 walls. In addition, it is not as simple as saying why don't you just extrude the first level wall so that it reaches to the top of the ceiling of the second floor. This is because some of the walls on the first floor are not same length as with the second floor walls. So another words, lets say maybe one of the first floor walls is 12 feet long and maybe only 7 feet of that 12 foot wall extends all the way to the top of the second floor ceiling and the other 5 feet only extends to the ceiling of the first floor.

So my question is, what would be the best way of getting seemless 2 story wall? Should I just extrude the first floor wall anyways and then boolean out the area I don't wan't from the second floor?