Fire Protection in Blocks of Flats Â– Pt 2a Â– Effective Compartmentation
Compartmentation is a method of fire separation within blocks of flats which is essential. A fire risk assessment will take into account the standard and maintenance of the compartmentation in a block and how effectively it would prevent the spread of fire between individual flats, flats and common areas and those areas and utility areas such as plant or boiler rooms.
Although compartmentation has been an essential part of fire protection in blocks of flats for many decades, standards prior to the 1960s in particular are very different from the standards expected today. These variations in standard do not necessarily mean that a block built prior to the 1960s (or indeed since, as compartmentation standards have continued to change) is not fire safe, but rather that certain amendments, maintenance or other updates to the fire prevention of the block may be necessary.
In new blocks of flats, the current standards state that each floor and wall of every individual dwelling within the block should be constructed with fire resistant materials which meet the standard. Additionally, every wall of a flat which is adjacent to a common area or corridor and the walls of each refuse storage room or boiler room.
The minimum level of fire resistance for a new purpose built block can vary, dependent upon the size of the block. For high rise blocks, the time which materials can withstand fire for may be in excess of 60 minutes, for most blocks, 30-60 minutes is usual and for smaller two-storey blocks, 30 minutes may be acceptable.
In older blocks of flats, it was common for 30 minutes to be considered adequate. However, the type of construction of some older blocks can mean that this estimate of 30 minutes is overly generous and that this level of fire resistance is not assured.
Current benchmarks relating to existing blocks of flats give the following as the minimum fire resistance for compartmentation:
2/3 storey buildings - notional 30 minutes fire resistance – typically timber floors with lath and plaster ceilings.
4/5 storey – full 30 minutes fire resistance – typically timber floors with plasterboard ceilings.
6 storeys and above – 60 minutes fire resistance.
In blocks where these benchmarks cannot be met, it is therefore important that compensatory measures are taken to improve the fire protection within a block. This may take the form of improved means of escape through either upgrading the construction and doors to current standards for escape corridors/stairs or through the provision of a fire detection and alarm system, or sprinklers to control/extinguish a fire.
Next week’s blog will continue to discuss effective compartmentation for fire safety in blocks of flats with a look at assessment of the existing condition of compartment walls and floors.
In the meantime, if you have any questions about this blog, or wish to discuss your new project or your fire risk assessment, please contact Peter Gyere in the first instance on 0208 668 8663.
The Complete Fire Safety Management Platform is the only fully comprehensive online fire risk assessment and fire risk management platform. Our aim, at CFSM, is to make the process of becoming fire safe, straightforward and, to use our expertise in fire risk assessment and fire safety management to guide you through each step, resulting in your premises meeting all legal, insurance and ethical fire safety considerations.