Preferably, a low profile location, away from obvious hazards such as water, fuel stores, high voltage electricity and vibration sources.

Where possible have another floor above the room – roofs leak – and remove fire and water hazards from adjoining areas and floors.

Any rainwater downpipes need to be sealed, boxed-in and isolated so that leaks will not flood the room space.

Drain access traps, manholes and the like, need to have double seals and screw-down covers.

Condensate drains need to be run in brazed jointed copper pipework and/or routed to leave the room as soon as soon as possible.

Non-gravity drains need dual run/standby pumps housed in watertight containers – inside the room or in an adjacent secure area
Drain traps exposed to room conditions will dry out and should be sealed.

A drain point in the room slab should be available for the removal of water in the event of a flood.

Valley gutters occurring above, or even in close proximity to the room need special attention to prevent leaks. The gutter itself should be underlined, to catch any leaks. The gutter and its outlets should be regularly cleaned and maintained.

It should be checked that an overflow facility is incorporated in the roof gutter design such that rainwater cannot build-up in the valley, regardless of the condition of the rainwater downpipes and the surface water or combined drains into which they are connected.

Special attention needs to be paid to symphonic roof drainage systems in which high pressures develop in small-bore pipes. They depend on a high degree of maintenance both above and below ground and are severely affected in the event of seals breaking or ground water flooding the underground chambers into which they discharge.

Walls need to be a minimum of 1Hr fire resistant and decorated to provide Class O flame spread. When 2Hr separation is called for, its restrictive effect on access to the room via similarly fire rated doors needs to be considered.

Where applicable, blast resistance needs to be taken into account when construction materials are chosen.

Seal
When the room is large enough for the floor void to be used as an air plenum, the floor slab needs to be insulated and its surface sealed against dusting whilst exposed to air circulation.

Strength
It needs to have structural strength sufficient to support the weight of UPS batteries and data safes. The reminder of the equipment is likely to be of little structural consequence.

Should a raised floor be installed, it needs to have structural construction such that it will support and distribute the superimposed point loads exerted by the floor pedestals– in order not to permit punching shear or collapse.

Vibration
The rigidity of the slab should be such as not to transfer vibration into the room from external sources. Otherwise its perimeter should be isolated in the case of RC construction; and mounted on anti-vibration pads in the case of steel frameworks.

Seal
It needs to be watertight/proof.

Strength
In the case of the ceiling slab being a floor for the area above it – see Floor slab. It needs to be structurally capable of supporting the load of a suspended ceiling, its insulation, light fittings, gas flood, refrigeration pipework and cable distribution.

Penetrations
In the case of a roof, any roof lights should be blocked out by either replacement with roof sheeting, or by the application of solar reflective paint.

Vent ducts and the like in a roof are a source of rainwater ingress. They should be removed or their weatherproof integrity checked and safe maintenance access to them ensured.

Doors contained in the perimeter walls of the room need to be solid cored and fire resistant to the same rating as the walls in which they occur.

Vision panels need similar fire rating.

Door furniture needs to conform to the requirements laid down for fire doors.

Door locks shall not hinder exit from the room in the event of a fire alarm. Either the locks will be operable from inside the room or fail safe.

External windows are unnecessary. They are environmentally hostile to the space and should be sealed and blocked in.

Internal viewing windows need to be constructed to achieve the same fire rating of the walls in which they occur.

A clearer view through –in the case of display areas, is achieved by inclining them.

Suspended ceilings need to be non-dusting and acoustically absorbing.

Free access behind is required for service and maintenance, as well as for use of the void for the passage of cabling or air.

Walls need to have Class O flame spread. In practice, this means that they may be decorated with emulsion paint or vinyl wall cloth.

The relative cost of each depends on the obstacles; in terms of wall mounted equipment and partition cover strips.

Vinyl emulsion provides a surface that can be cleaned as easily as wall cloth. It is however easier to maintain.

Strength
The raised modular floor should comply with the relevant MOB Grading Standard.

Local reinforcement is always possible for isolated items – such as data safes.

Stability
Mechanical fixing of the pedestals to the subfloor is necessary when the floor height exceeds a certain level. This is to prevent floor collapse when loads are being moved whilst tiles are not in place. Interesting problem when the subfloor comprises woodblocks! Underfloor void obstacles such as drain covers and buried services ducting may be bridged with steelwork to permit the uninterrupted layout of floor pedestals.

Consideration regarding service access needs to be built into the design of such bridging.

subfloor strengthening may be required in the case of certain types of construction – to spread the point loads and prevent punching shear.

Finish
The surface covering of the floor panels needs to be non-static forming and non-dusting.

Carpet finishes will shed fibres, but also hold particulate within their pile and absorb sound.

PVC coverings shed small amounts of fine particulate and do not hold dust. They also reflect sound.