In April of 2012, the Al Tayer tower in Sharjah, UAE burst into flames, crumbled and crashed to the ground flatter than a pancake. This was one of over 1,000 fires in Dubai with unknown causes; many of these fires were in skyscrapers.
The Al Tayer tower was not the last time such an incident occurred either. In November 2012, the Tamweel Tower in Dubai followed suit, and then the Al Hafeet tower in April 2013. Luckily, there were few casualties, but in all three cases, the entire tower was engulfed in flames. All of these occurrences had one thing in common: flammable aluminum facades.
First, why did the facades burn? According to the BBC, the origin of the problem is the aluminum catching fire – the facade consists of a combustible thermoplastic core between two sheets of aluminum (Law 2013). All it takes to ignite something inside the tower is a dropped cigarette or unattended barbecue (Law 2013), and the facades will be the next to go. When a fire starts, the core is the first to go, and then the aluminum can catch fire and melt (at 1220.581°F). Although melting is unlikely (as it require very high temperatures, aluminum begins to weaken at a mere 212°F (AluminumDesign.net), while the steel used in many high rise buildings such as China's Ping An Finance Center does not weaken until 797°F (Eagar, Musso 2001). Once the aluminum has begun to weaken, even if the metal itself is not yet burning, it is very easy for hot pieces of metal, burning chunks of plastic or other building materials to fall to the ground and kill passersby (Law 2013). Finally, the weakened layers of the building soften and give way, and the entire tower can crash to the ground in a heap. Finally yet importantly, aluminum is a very chemically reactive metal (according to the reactivity series) (Jarman). Thus, the aluminum facades would easily react with the excess oxygen, speeding up the blazes.
Secondly, why is this important? What ethical factors are there to consider in this problem? Of course, people's lives are at stake. Hundreds and thousands of people use these structures daily, so leaving the buildings unsafe is completely unethical. Furthermore, not only the people inside the tower were threatened: at the Tamweel Tower blaze, flaming pieces of the tower hurtled to the streets below (Law 2013). After all, skyscraper fires have occurred before, and there will probably be more such fires in the future. The most we can do is make our towers as safe as we can. Unfortunately, refitting the 500-odd towers in the UAW with flammable facades presents an economic hurdle, but builders might have avoided the makeovers if the UAE had more detailed legislation about skyscraper safety. The UAE only passed such laws after the Al Hafeet tower burned down (Law 2013), whereas the US prohibits the aluminum facades in buildings over four stories and the UK has not touched such materials since the 1980s (Law 2013). Nevertheless, other than remodeling dangerous structures, a proper...