What does raised floor mean?

A raised floor is a data center construction model in which a slightly higher floor is constructed above the building's original concrete slab floor, leaving the open space created between the two for wiring or cooling infrastructure.

Areas Typically Most Suitable for Raised Floor Systems

Computer rooms and other information technology spaces.

General open office areas.

Training and conference areas.

Exhibit spaces.

Support spaces for offices, including electrical closets, fan rooms, etc.

Clean rooms

Areas Not Suitable for Raised Floor Systems

Slab on Grade Locations

Raised floor system is not suitable to be placed directly on the slab on grade. This is because protection against heat, contaminant, and moisture that transferred with soil, soil gas, and groundwater cannot be achieved for a long period.

Toilets, Showers, Baths, Dishwashing, and Other Wet Area

Plumbing fixtures are commonly installed in these areas which may leak and lead to the corrosion and deterioration panels.

Kitchen and Food Preparation Areas

High humidity and possible spillage food and liquids and seepage make these areas inappropriate for such types of floor systems.

Laboratories

The likelihood of chemical and biological spills in addition to moisture and the presence of plumbing make laboratory unsuitable for a raised floor system.

Fire Stairs

Stair landings need an interface with any adjacent raised floors as a flush condition with the edge of the access floor well supported.

Mechanical Equipment Rooms

Examples of such rooms involve air handling equipment, chiller, and boiler. it can be noticed from their names that these rooms have conditions in which panels of raised floor systems will deteriorate and damage.

Other areas include Central storage rooms and loading areas, trash rooms, UPS, emergency generator, and similar rooms, and Childcare.

Why do data centers have raised floors?

In data centers, isolated air-conditioning zones are often associated with raised floors. Perforated tiles are traditionally placed beneath computer systems to direct conditioned air directly to them. In turn, the computing equipment is often designed to draw cooling air from below and exhaust into the room.

What types of raised floor system are available?

Raised floor panels vary in construction materials, depending on your application. Abeite raised floor  include:

Calcium sulphate panels 

Wood core panels

Anti-static Concrete core steel panels

Bare concrete panels

Aluminum Access Floor

Air-flow panels

Glass viewing panels

What types of covering finishes are available for raised flooring?

Panels may be covered with a variety of flooring finishes to suit the application, such as carpet tiles, high-pressure laminates, PVC, marble, stone, Ceramic, Parquet, Rubber, Linum and antistatic finishes for use in computer rooms and laboratories.

How much weight can a raised floor support?

Calculate the floor loads for your server with these formulas.

A floor loading assessment is the evaluation of the concrete subfloor, not the raised floor. The weight of the raised floor is considered in the floor loading formula.

The building floor must support the weight of the equipment to be installed. Although older devices might impose 345 kg/m2 (75 lb/ft2) on the building floor, a typical server design imposes a load of no more than 340 kg/m2 (70 lb/ft2). The following pounds-per-square-foot (lb/ft2) formula is used to calculate floor loading. For assistance with floor load evaluation, contact a structural engineer.

Floor Loading is: ( machine weight + (15 lb/ft2 x 0.5 svc clear) + (10 lb/ft2 x total area))/ total area

The floor loading should not exceed 240 kg/m2 (50 lb/ft2) with a partition allowance of 100 kg/m2 (20 lb/ft2) for a total floor load rating of 340 kg/m2 (70 lb/ft2).

The raised-floor weight plus the cable weight adds 50 kg/m2 (10 lb/ft2) uniformly across the total area used in calculations and is included in the 340 kg/m2 (70 lb/ft2) floor loading. (The total area is defined as machine area + 0.5 service clearance.)

When the service clearance area is also used to distribute machine weight (weight distribution/service clearance), 75 kg/m2 (15 lb/ft2) is considered for personnel and equipment traffic. The distribution weight is applied over 0.5 of the clearance up to a maximum of 760 mm (30 in.) as measured from the machine frame.

The raised floor on which the system will be installed must be capable of supporting the system's weight. Contact the raised floor tile manufacturer, a structural engineer, or both to verify that the raised floor is safe to support a concentrated load equal to one-third of the total weight of one rack on a single raised floor tile. Under certain circumstances, such as relocation, it is possible that the concentrated load on a single raised floor tile can be as high as one half of the total weight of one rack per caster. When you are installing two adjacent racks, it is possible that one caster from each rack can be placed on the same raised floor tile. The load on the raised floor tile can be as high as one-third of the total weight of both racks.

Depending on the type of raised floor tile, additional supports, such as pedestals, might be necessary to maintain the structural integrity of an uncut tile or to restore the integrity of a tile that is cut for cable entry or air supply. Contact the raised floor tile manufacturer, a structural engineer, or both to ensure that the raised floor tiles and pedestals can support the concentrated loads.

** Note: The above explanation from Wikipedia

What is the expected lifetime of a raised access floor?

The expected life span of a raised access floor system is outlined in the PSA MOB PF2 PS / SPU specification as:

· The supporting components should have a minimum life of 50 years.

· The floor panels (excluding floor finish) should have a minimum life of 25 years.

Seismic Conditions Requirements of Raised Floor System

The specified raised floor system needs to comply with the following conditions (as a minimum):

For seismic zone 3 and higher seismic zones, it is required to use bolts for fixing pedestals. Commonly, manufacture specifies the suitability of pedestal for seismic zones.

It is required to use bracing for pedestals provided that their length is greater than 30.48cm and used in seismic zone 3 and greater.