Early on the morning of June 14, 2017, a fire broke out at the 24-story Grenfell Tower apartment building in London. The assumption underlying Grenfell Tower’s stay-put fire safety policy – flames would be contained to a single unit due to the high rise’s concrete construction and fire-resistant doors – proved to be wrong. The fire quickly engulfed the building exterior, resulting in the loss of 72 lives.
In the aftermath, investigators scrambled to determine how a small fire could reach such deadly proportions, finding that the siding product used on the Grenfell Tower greatly contributed to the spread of the fire.
The Culprit: Aluminum-Polyethylene Siding
Installed during a renovation of Grenfell Tower in 2016, the siding in question consisted of aluminum sandwich plates and a polyethylene core, which created a “chimney effect” through which the fire quickly swept upward after finding its way into a space between the aluminum panels and the building. This caused the fire to spread across much of the facade within 10 minutes of the initial call to the London Fire Brigade. Tests conducted on the aluminum-polyethylene siding after the fire also revealed that its polyethylene panel was flammable.
UK Government Action
In May 2018, Prime Minister Theresa May promised approximately $500 million in government funding for housing associations to replace similar siding used on other high-rise residential buildings with regulation-compliant materials. This money is being allocated to public housing only, leaving private building owners to cover the cost themselves. Recent actions taken by the UK Housing Secretary give new powers to district councils to make sure that they do.
A number of other actions have been taken to address safety concerns about combustible siding:
- Arconic (formerly Alcoa), the supplier of the cladding used on Grenfell Tower, discontinued this product soon after the fire.
- In October 2018, the UK government announced a ban on the use of combustible materials in cladding installed on new residential buildings taller than 18 meters, as well as on schools, care homes, student accommodations, and hospitals.
The UK Fire Brigades Union warned that this ban is insufficient because it continues to allow the use of semi-combustible Class A2 materials such as plasterboard, and it does not require the hundreds of buildings in the UK still wrapped in the flammable cladding to be retrofitted with acceptable materials.
However, a change to housing health and safety regulations announced in November 2018 will enable local governments to strip dangerous siding materials off private buildings themselves and bill the owners for the costs, effectively coercing compliance as landlords continue to drag their feet.
Actions Elsewhere in the World
The tragedy of the Grenfell Tower fire has served as a cautionary tale outside of the UK, as well. In Australia, for example, multiple states have enacted bans on siding containing combustible materials.
Furthermore, the fire safety provisions of the International Building Code – which is followed in the UK – had previously allowed use of siding with a combustible polyethylene core on buildings more than 40 feet tall without fire-testing as long as the building contained sprinklers. After the Grenfell Tower fire, however, the International Code Council (ICC) decided to reexamine the issue, and in 2018 began taking steps to require the fire-testing of buildings that use this siding regardless of the presence of sprinklers.
Additional regulation may also be forthcoming. For example, the ICC is also considering whether to restrict use of metal composite material in high-rise cladding in its next update because of the Grenfell Tower tragedy.
To Learn More
For more information on how regulatory changes and other factors are expected to impact the global siding market, download Global Siding (Cladding), a recent report from The Freedonia Group.
About the Author:
Nick Cunningham is an Industry Analyst at the Freedonia Group where he covers the US and global construction and building products industries.