Building, highrise, cladding

Primary reference(s)

Rockpanel, no date. What is a high rise or high-risk building? Accessed 8 November 2019.

Additional scientific description

Building height is an important factor in fire safety. The National Fire Protection Association defines a ‘high-rise building’ as a building greater than 75 feet (25 m) in height where the building height is measured from the lowest level of fire department vehicle access to the floor of the highest occupiable story (OSHA, 2003). The definition of what constitutes a high-rise building differs for many European countries. For example, in Germany, high-rise buildings are those 22 m and above, in Belgium 25 m and above, and in the UK 18 m and above. Despite the exact limit, it is indisputable that risk increases with increasing building height (Rockpanel, no date).

Escaping from tall buildings is more difficult and takes longer than from a single-family house with one floor. Not only do highrise buildings have more inhabitants or people that work in them, but normal houses also have more escape routes (windows, doors) making escape easier when a fire occurs (Rockpanel, no date).

Composite panels were first developed as a cost-effective, lightweight building material that could be rapidly installed for external cladding or facades of industrial buildings. Following considerable development over recent decades, these panels are now widely used across a vast range of buildings. The main advantage of composite panels is that they are inexpensive, can be easily cut and shaped in any size or dimension, are lightweight, and have excellent insulation characteristics. The products also come with a wide variety of surface finishes to suit architectural designs. The issue of combustible composite panels now concerns both private residences and commercial offices and factories (Chen et al., 2019).

Recent high-profile building fires involving highly-combustible external cladding panels in Australia as well as Dubai, China, and the United Kingdom have created a heightened awareness by the public, government, and commercial bodies of the need to act on the risks associated with non-compliant building structures (Chen et al., 2019). The history of fire incidents involving combustible external composite panels goes back many decades and includes well documented events such as: the Knowsley Heights Fire in Liverpool UK, 1991; the Garnock Court Fire in Scotland, 1999; the Television Cultural Centre Fire in China, 2009; the Shanghai Apartment Fire in China, 2010; the Tecom Building Fire in Dubai, 2012; the Lacrosse Building Fire in Australia, 2014; The Torch in Dubai, 2015; The Address in Dubai, 2016; and Grenfell Tower in the UK, 2017 (Chen et al., 2019).

The Grenfell Tower fire broke out on 14 June 2017 in the 24-storey Grenfell Tower block of public housing flats in North Kensington, West London, United Kingdom. The London Metropolitan Police confirmed that 80 people died as a result. Prior to the incident, Grenfell Tower underwent a major renovation on the exterior of the building which included new windows, a heating system, and the installation of a new exterior cladding for insulation and rainscreen. The fire is believed to have been started from a refrigerator in a 4th floor apartment kitchen. The residents were in the apartment at the time and called the fire brigade. Despite firefighters arriving 6 minutes after the alarm, the fire managed to spread to the exterior cladding before the firefighters suppressed the kitchen fire. The flames spread at an alarming rate up the exterior cladding and the fire quickly became out of control. In addition, the exterior fire re-entered the building, trapping a significant percentage of residents inside the building (Chen et al., 2019).

In its report, the UK Ministry of Housing, Communities and Local Government stated that Aluminium Composite Material (ACM) cladding (and other metal composite material cladding) with an unmodified polyethylene filler (category 3) presents a significant fire hazard on residential buildings at any height with any form of insulation (Ministry of Housing, Communities and Local Government, 2020).

Metrics and numeric limits

Not identified.

Examples of drivers, outcomes and risk management

Appropriate exits, alarms, emergency lighting, communication systems, and sprinkler systems are critical for resident and employee safety. When designing and maintaining exits, it is essential to ensure that routes leading to the exits, as well as the areas beyond the exits, are accessible and free from materials or items that would impede individuals from easily and effectively evacuating (OSHA, 2003).

Since the tragedy at Grenfell Tower, the UK government’s Building Safety Programme has focussed on identifying and advising on short-term interim and remedial measures for existing high-rise residential buildings with ACM cladding, while developing wider reforms for the future building safety regulatory system (Ministry of Housing, Communities and Local Government, 2020).

In October 2019, Phase 1 of the Grenfell Tower Inquiry reported on the role played by ACM cladding, fitted onto the exterior of the building. Sir Martin Moore-Bick, the Chairman of the Inquiry, found that the “principal reason why the flames spread so rapidly up, down and around the building” was the presence of combustible ACM cladding, “which acted as a source of fuel” (National Audit Office, 2020).

In the wake of the Grenfell Tower disaster, the Ministry of Housing, Communities and Local Government, UK, established the Building Safety Programme (the Programme) “to ensure that residents of high-rise residential buildings are safe, and feel safe from the risk of fire, now and in the future”. While remaining clear that it is building owners who are responsible for ensuring the safety of their buildings, the Department has adopted an objective to “oversee and support the remediation of high-rise residential buildings that have unsafe aluminium composite material cladding”. The Programme is designed to implement this objective, as well as to reform building regulations and the construction industry in the light of flaws brought to light in the wake of the Grenfell tragedy (National Audit Office, 2020).