I was a smart alec at first and said they must have had rockets mounted on the building pointed toward the ground to make it fall faster.
Eventually I just pointed out that objects only fall so fast. The laws of physics dictate that a falling object reaches terminal velocity and falls no faster PERIOD.
Actually the principle was demonstrated during one of the moon landings. The astronaut dropped a heavy object and a feather at the same time and they both fell at the same rate.
I would look up "Terminal velocity" with Google for a detailed explanation.
The problem is that in atmosphere each object has a differing terminal velocity. In atmosphere, that feather would fall far slower than a rock.