The first floor of the NetApp data center houses the server area. Rather than an open floor, NetApp's design features a series of enclosed data rooms that are accessible through a center entrance hallway (pictured above). Each data room uses cold-aisle containment and overhead air distribution. Instead of pumping cold air up through raised floors, overhead air distribution takes advantage of cold/hot air buoyancy and eliminates ductwork, which reduces energy needed for fans. This also reduces construction costs as raised floors are expensive to build.