Tom,
You can even reduce the footprint more by building against a wall as a facade or reducing the depth of the building by putting it against a wall.
Billy,
Some of the pictures I looked at showed the floor open. In the case of electric furnaces, everything appears to take place in inside a closed building. Blast furnaces are definitely more sexy than modern electric furnaces.
Again I would do like to say thank you all for the nice comments. I would now like you all to start building blast furnaces on your layouts.