The client said, "We've got this building located underground with 2-ft concrete walls; it was originally designed as an emergency telephone switching facility built to withstand a nuclear blast. That was 30 years ago. Now we're adding new telephone equipment and the existing infrastructure won't be able to handle the additional load. The mechanical equipment is all original, and most of it needs to be replaced. Our temperature control system isn't doing much for us, just monitoring and alarming - the entire system should be replaced with contemporary technology. We don't have city water service, and our fire protection system won't be big enough to handle anything more, so it'll need to be addressed. Fire detection is antiquated and needs to be upgraded. Electrical service from the utility is pretty much maxed out. Our main transformer may need to be replaced.
By the way, we need to do all of this without shutting anything down. Ever."