I was looking at some drawings in one of my dad's friends house and he had a drawing of a 15 story building. This building was weird though, the first couple of floors were much bigger than the top floors. the floors kept getting smaller and smaller as they went up. I saw that not all the square footage was present on this drawing, so I guessed like a 1/3 of it. I came up with 456,000 square foot. Do you guys think thats a lil big?? or am I just stupid. I could have sworn that when I read apartment complex drawings there was only like 150,000 square foot in about 120 units. Whats the common size of these type of buildings?