As the owner will naturally desire to obtain as many floors as possible, it will be necessary to consult, first of all, the building laws of the city in which the building is erected, to determine the height to which our building may be carried. This determined, the number of floors must be decided. As the lower floors are less likely to be subdivided than the others, they must be given a height which will be in proportion to the probable size of the rooms, so that the height of the lower stories must be added together, and the sum, with the addition of the thickness of the floors, must be taken from the whole height of the building before we can establish a unit of height for the rest of the stories.