Fire Safety for High Rise Buildings with Flammable Cladding
It is generally thought that those on higher levels of high rise buildings are more at risk from fire than those on lower levels. However, this is a common misconception and there is no evidence to support this. Since the Grenfell tragedy in 2017, people are naturally more wary of living in high rise buildings. Even more so if they are clad in flammable materials.
Whilst official figures show there are 300 tower blocks with Grenfell style cladding awaiting removal works, it’s estimated that there are around 1700 buildings in total in the UK with dangerous combustible materials on their facades.
Previously such buildings had a Stay Put fire safety policy. However, buildings with dangerous cladding are now required to change their fire strategy to Simultaneous Evacuation. Simultaneous Evacuation means that residents are all evacuated at the same time. It also requires a means to alert building occupants of the need to evacuate the premises.
So what is the answer to ensuring the fire safety of residents in these types of buildings? To enable Simultaneous Evacuation, temporary fire safety measures are required until the cladding and other combustible materials are removed. The National Fire Chiefs Council (NFCC) recommends a 24/7 waking watch service or the installation of a fire detection system.
What is a Waking Watch?
A waking watch is defined as “a system whereby suitably trained persons continually patrol all floors and the exterior perimeter of the building in order to detect a fire, raise the alarm, and carry out the role of evacuation management.”
Figures from 40 fire authorities in the UK indicate that there are as many as 420 ongoing waking watch services in place, some in place for years and some dating right back to the time of the Grenfell fire.
Fire Detection Systems in High Rise Buildings
Whilst the Regulatory Reform (Fire Safety) Order 2005 applies to the common parts of blocks of flats, communal areas don’t usually incorporate a fire alarm system. However, when a Simultaneous Evacuation is required, the NFCC recommends installing a fire alarm system throughout the building designed to meet BS5839 part 1 category L5. Individual flats or apartments within the building are then protected by part 6 devices. The part 1 fire alarm system provides protection for all communal areas defined in the fire strategy. The system is then interfaced with the part 6 devices in the separate apartments to create a single engineered fire detection and alarm system.
Waking Watch or Addressable Fire System?
The immediate fire risk in buildings with flammable cladding needs to be addressed urgently to ensure occupants’ fire safety. Whilst a waking watch service can be put in place very quickly, the associated costs of this soon mount up. A recent Government publication on waking watch costs showed the average monthly cost in England to be almost £18,000 per building. This equates to almost £215,000 per year and to over £300 per month per dwelling.
The amount of time for remedial works to be completed on removing the dangerous cladding can be at least 3 years. With the current Covid-19 pandemic, this time has only been seen to increase. Given this consideration, the installation of an addressable fire alarm system becomes a much more cost-effective, viable option.
Given these costs over at least the next three years, it’s evident to see why an addressable fire alarm and detection system becomes the preferred option. According to Government research, the cost of a new fire alarm system, depending on building size, is between 3-6 month’s fees for a single waking watch guard.
Given that official fire chief’s guidance governing the use of waking watch services says their presence without the back up of a fire alarm and detection system is the “least reliable” means of providing an alert in the event of a fire, as well as being “the most resource intensive” further backs up the rationale for a fire system installation. The same guidance also states that a waking watch service is “impracticable for a long-term solution and should only be a short-term measure”.
Fire Safety following Cladding Removal
Fire alarm systems are generally not fitted in high rise residential buildings and was actively discouraged in government-backed guidance published in 2011 that said fire alarms “should not be installed unless it can be demonstrated that there is no other practicable way of ensuring an adequate level of safety”.
Break glass devices in corridors can be easily triggered either by accident or by vandals, and individual apartment detectors can trigger full evacuations from simple acts such as burning toast.
However, there are now fire alarm systems that incorporate hush buttons within flats to eliminate false alarms. Smarter fire alarm systems activated by heat or multiple smoke outbreaks also help to filter out false alarms from actual fires
Once the remedial works are completed and all flammable cladding and other combustible materials removed from a building’s structure, the original Stay Put fire strategy can be reinstated once the fire risk assessment and strategy has been reviewed and all stakeholders are in agreement through consultation.
However, this then leaves a fire alarm and detection system in place. This can be left in situ to complement the existing Stay Put policy and maximise fire safety for the residents. An alternative is to adapt the system to be used as an evacuation system. BS8629 recommends installing an evacuation system for use by the Fire & Rescue Service to advise residents how to evacuate in the event of a fire. If the long-term fire strategy for the building is to adopt this guidance, the necessary infrastructure to convert the system to an evacuation system can be incorporated into the design of the temporary fire alarm system. It must be stated though that if a fire alarm system is converted for use as an evacuation system, it is no longer able to be used as a fire alarm and detection system under BS5839 and will no longer provide automatic fire detection.
Why choose Triple Star Fire & Security?
Installing an addressable fire alarm and detection system is far more cost effective long term than a waking watch service. Triple Star Fire & Security have recently been installing compliant fire alarm systems in such buildings. We can help you choose the correct fire detection solution for your building, ensuring your fire safety strategy is in place correctly and residents are fully protected from the risk of fire.