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Last edited 04 Apr 2019
Suspended ceilings are secondary ceilings suspended from the structural floor slab above, creating a void between the underside of the floor slab and the top of the suspended ceiling. The gap between a suspended ceiling and the structural floor slab above is often between 3 to 8 inches which is why they are often referred to as dropped ceilings or false ceilings.
Suspended ceilings are very popular in commercial properties as they provide a useful space for concealing unsightly wires and installations that otherwise would alter the interior appearance of the building.
The space gained through installed a suspended ceiling has proved useful for distribution of heating, ventilation and air conditioning (HVAC) services and plumbing and wiring services, as well as providing a platform for the installation of speakers, light fittings, wireless antenna, CCTV, fire and smoke detectors, motion detectors, sprinklers and so on.
 How are suspended ceilings installed?
Once the dimensions have been accurately taken, the drop of the ceiling needs to be determined to measure around the perimeter of the room. By effectively measuring and marking the drop of the ceiling, this prevents any nasty surprises when the grid is fitted.
The false ceiling is hung from a bracket fixed to the underside of the floor slab, supporting a series of interlocking metal sections that form the grid. Beam systems are also available, in which tiles are laid between parallel beams rather than a grid, and there are a wide range of different grid profiles and tile edge details that can be used to allow the grid to be exposed, flush, recessed or concealed.
The different tiles available come in a variety of designs, colour and materials. The huge variety available means that there will be something for everyone when looking at changing the interior appearance of a property.
Tiles may be manufactured from materials such as mineral fibre, metal, plasterboard and laminates and are often perforated to provide specific levels of acoustic absorption that can be used to control the reverberation time in spaces below. Typically ceiling tiles are 600mm by 600mm or 600mm by 1200mm, although a range of sizes are available, as well as bespoke panels such as moulded panels, and complex systems that might include acoustic baffles, dropped panels, integrated service modules and so on.
Once a suspended ceiling has been installed, partitions can additionally be installed to optimise space for convenience. Similar to suspended ceilings, partitions can be designed in a variety of styles to suit the appearance and atmosphere of the interior space.
Partitions can be neatly integrated with suspended ceilings by stopping underneath the false ceiling or running straight through to the structural floor slab above. Together with suspended ceilings, partitions create a modern design that complements commercial properties.
However, when partitions are installed, it is crucial that safety measures are conducted to ensure that a flanking path is not created for the transmission of sound between adjacent spaces or for the spread of fire. Acoustic insulation or fire separation can be provided in the ceiling void if necessary.
The selection of suspended ceilings may depend on:
- Aesthetic considerations.
- The requirement to incorporate fittings necessary for building services.
- Requirements for acoustic attenuation and absorption.
- Hygienic requirements.
- The need to provide fire separation.
- Moisture resistance
- Corrosion resistance
- Cleaning requirements.
- Thermal insulation.
- Tile thickness and size.
Approved Document B2, ‘Fire safety: Buildings other than dwellinghouses’, defines a suspended ceiling (fire-protecting) as '...a ceiling suspended below a floor, which contributes to the fire resistance of the floor'. Appendix A, Table A3 of the approved document classifies different types of suspended ceiling.
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