Access floor

Araised floor(alsoraised flooring, access floor(ing), orraised access computer floor) provides an elevated structuralfloorabove a solid substrate (often a concrete slab) to create a hidden void for the passage of mechanical and electrical services. Raised floors are widely used in modernoffice buildings, and in specialized areas such ascommand centers,ITdata centersand computer rooms, where there is a requirement to route mechanical services and cables,wiring, and electrical supply. Such flooring can be installed at varying heights from 2 inches (51 mm) to heights above 4 feet (1,200 mm) to suit services that may be accommodated beneath. Additional structural support andlightingare often provided when a floor is raised enough for a person to crawl or even walk beneath.

The general types of raised floors in telecommunications data centers include: stringerless, stringered, and structural platforms; and, truss assemblies.

• Stringerless raised floors— an array of pedestals that provide the necessary height for routing cables and also serve to support each corner of the floor panels.
• Stringered raised floors— a vertical array of steel pedestal assemblies (steel base plate, tubular upright, and a head) uniformly spaced on 2-foot centers and mechanically fastened to the concrete floor.
• Structural platforms— members constructed of steel angles or channels that are welded or bolted together to form an integrated platform for supporting equipment.
• Truss assemblies— utilizing attachment points to the subfloor to support a truss network on which the floor panels rest. The truss has high lateral strength and transfers lateral loads to the subfloor with less strain than possible with a vertical pedestal assembly.