[USSGahagan]

I work for a real estate developer, but I am not familiar with construction, so I have a few questions regarding the use of steel vs. reinforced concrete when building high rises.

I have seen new office buildings in Orange County being built out of Steel and residential towers being built out of reinforced concrete. Why the difference? Is reinforced concrete a better product for residential? Is there a big cost difference between the two skeletons? Given that California shakes, are seismic concerns an issue for one but not the other after certain heights? Thanks.