And security, access control, network connectivity and
layout, cooling
 types, hot/cold aisles, UPS provision, building and energy
 monitoring/management systems, server monitoring, KVMs/console servers,
 space allocation. ?Yes, quite a lot is common sense but there's a lot to
 consider and plan, and some of it needs expert input if only for reasons of
 compliance. ?(I know, we built two new ones in the last two years). 
And planning ahead for maintenance, upgrades, decommissionings*, etc..
See, it is not so simple.
--
Will, *who once had to Sawzall an big RS/6000 to get it out without
breaking a FDDI ring.