So, a thing to remember when drawing structures that are 'under construction', that people might not think about, is that when we're talking about early stages (beams and what not), these buildings are put up one floor at a time.
That is, you won't see like, a phone connection diagram that resembles a set of stairs. It's going to be flat up to a certain level, and then the construction will be happening. After all, you have to finish one level to start another.
Also, if it's a particularly tall building you're going for, there will be a big crane in the middle of the building. Shorter buildings will have ground based cranes, but the real big ones have cranes that raise as the building does. What's really important to remember though, is that if you're adding steel to a building, you're going to have a crane. You can't just get a bunch of workers to haul that stuff up on their shoulders.