What is mezzanine floor fire protection and why is it necessary?
So called ‘fire protection’ is effectively warmth of the mezzanine floor steelwork to prevent it from warming up quickly in a fire. Unprotected steelwork gets hotter quickly and can suddenly collapse. Fire protection is specified for a certain period of time such as ‘half hour’, ‘1 hour’, ‘2 hour’ or ‘4 hour’. The timeframe làm gác xép refers to the time that the protected elements remain structurally sound in the event of a fire. The fire protection required for some other part of buildings is specified within the Building Regulations part B.
Fire protecting building elements in accordance with the regulations is a statutory requirement, protecting lives and property and enabling the fire brigade to assess how long they can safely fight a fire before a risk of collapse.
Providing fire protection to mezzanine floors is likewise known as ‘fire rating’ them, and a mezzanine floor fitted with fire protection may be referred to as ‘fire rated’.
Do mezzanine floors always need to be fire protected?
The requirement for fire protection depends upon utilization, size and extent of the mezzanine floor. Mezzanine flooring that is less than 10m x 10m in size, and occupying less than 50% of the part of the building in which it is located and which is not permanently occupied and often accessed (used for storage) doesn’t need to be fire rated.
Mezzanine flooring that is less than 20m x 20m in size, and occupying less than 50% of the part of the building in which it is located and which is not permanently occupied and often accessed (used for storage) doesn’t need to be fire rated as long as it is fitted with an appropriate fire detectors and wireless home alarm.
Any mezzanine floors that are permanently occupied regardless of size will need to be fire protected such as office areas, assembly and manufacturing, packing, canteen space or areas such as retail space with public access. Also mezzanines larger than 10m x 10m without an appropriate fire detectors and wireless home alarm, all mezzanines larger than 20m x 20m and all mezzanines whose size exceeds 50% of the area within which are located. It can be seen that only in the smallest storage applications can fire protection be overlooked.
How is most mezzanine flooring fire protected?
The most common means of fire protecting mezzanine floors is through the use of four key elements of warmth, column casings, a suspended ceiling, bulkheads/fascias and hole barriers. This means of fire protecting mezzanine floors is used because of its speed of installation and low cost.
Column casings comprise a two part bed sheet metal case repleat with ‘Promalit’ or similar board bonded to the inside of the casing. The bed sheet metal case usually has a galvanized or white ‘plastisol’ finish to suit the appliance, but can be stainless-steel or coloured ‘plastisol’, and the two parts have an unobtrusive locking seam enabling them to be quickly and neatly fitted with a few taps from a rubber mallet.
Suspended ceilings comprise wires dangled vertically on films from the legitimate supports of the mezzanine supporting time ceiling athlete. The runners clip together and are joined in turn by intermediate diets of ceiling athlete to manufacture a ceiling grid. Minaboard tiles are then inserted to fill the grid. The grid is normally and most in the economy based around 1200mm x 600mm ceiling tiles, however by adding further intermediate 600mm ceiling runners, 600mm x 600mm tiles can be used. The tiles fitted must be certificated to provide hidden level of fire protection when used in the grid under a mezzanine floor. This restricts the available choice of tiles and finishes.
Bulkheads or fascias (vertical barriers to close up ceiling cavities to exposed perimeters at mezzanine floor edges or voids) are achieved by creating a framework from galvanized section and cladding the framework with plasterboard to obtain the required level of fire protection in accordance with the manufacturers specifications. Our bulkheads/fascias are then decorated.
Hole barriers are directory barriers within the ceiling void created with nutrient wool warmth to subdivide the void into compartments in accordance with the Building Regulations in order to prevent smoke or flame traveling through the ceiling void.
Alternative means of fire protecting mezzanine floors
Sometimes aesthetic or other considerations such as positive pressure fire extinguishing systems preclude the use of suspended ceilings. Alternatives include taped, jointed and decorated plasterboard ceilings on a metal furring (MF) ceiling framework and similarly boxed in articles providing flush finishes or intumescent painting of hot rolled articles and supports.
All the components of fire protection should be certified to provide the required degree of protection in the application in which they are being used. For example it is not acceptable to use any old suspended ceiling below a mezzanine floor; the ceiling tile and grid system must have certification specifically providing the required level of protection under a steel joist type mezzanine construction, which significantly restricts the range of manufacturers able to present you with a suitable product.
This general information relates to mezzanine flooring fire protection in He uk and is intended for guidance only. Each application needs to be assessed on its own merits.
It is always prudent to discuss your distinctive project with an approved inspector or building control officer prior to commencing work, an activity with which your mezzanine floor contractor will be prepared to assist.