Author(s): Angelo Verzoni. Published on August 30, 2021.

‘Totally Vulnerable’

After fire tears through a Milan apartment building, the high-rise’s cladding is now under scrutiny


On August 29, a fire destroyed a 20-story apartment building in Milan, Italy, and experts say combustible components in the building’s facade was likely the cause of how rapidly the blaze spread. 

Videos posted online show flames consuming the entire outside of the building in just over three minutes as large, smoldering chunks of the structure’s exterior walls break off and fall to the ground—an observation often seen in large-scale facade fires. Although it appears the building will be a total loss, no deaths or injuries have been reported. 

Comparisons to Grenfell 

In the hours following the recent Milan blaze, several building safety experts and non-experts alike shared their thoughts about how a combustible materials on the outside of the building likely fueled the fire. 

“The facade of the building was built with combustible materials,” Angelo Lucchini, professor of technical architecture at The Polytechnic University of Milan, told a local news outlet, according to The Guardian

“Is flammable cladding more common than we think?” wondered one person on Reddit, a popular social media, news, and discussion website. “How does the entire building go up like that otherwise?”

BEFORE & AFTER Images from Google Earth and Getty Images show the 20-story tower’s light-gray cladding before and after Sunday’s massive blaze.

Many people, including the mayor of Milan, likened the recent fire to the catastrophic Grenfell Tower fire, which killed more than 70 people in London in 2017. In that incident, cladding and insulation containing high levels of combustible plastics were blamed for the fire’s rapid spread. 

RELATED: Listen to an NFPA podcast about the Grenfell Tower fire, which marked its four-year anniversary in June

“What was clear from the start was that the building’s outer shell went up in flames far too quickly, in a manner reminiscent of the Grenfell Tower fire in London a few years ago,” Milan Mayor Beppe Sala wrote on Facebook, according to Reuters. “The tower was built just over 10 years ago and it is unacceptable that such a modern building should have proved totally vulnerable.”

A growing global threat 

Fires fueled by combustible exterior wall assemblies—which are often added to buildings to improve aesthetics and energy efficiency—used to be uncommon, but the number of incidents has risen drastically in the past 30 years, according to Birgitte Messerschmidt, director of Applied Research at NFPA. 

“According to research done at Imperial College in London, the frequency of facade fires in large buildings has increased by seven times in the last three decades,” Messerschmidt writes in an article published in NFPA Journal in May 2020. “Other researchers have identified 59 fires involving external walls on high-rise buildings between 1990 and 2018, with 36 of these occurring since 2010.” And as global trends favoring urbanization bring more people to cities and more high-rises are constructed to house those people, Messerschmidt said this problem will only get worse in the coming years. 


One of the first steps needed to address the problem is collecting more data about facade fires. “It is important to recognize that there is an opportunity to learn from failures, and even successes, and develop strategies based on real-world fire incidents,” Messerschmidt writes. “The education of stakeholders, growth from previous failures, and quantification of this global issue demand much more data than are currently available today.” 

Read the full article here, and watch a related video from NFPA Journal about facade fires below.

ANGELO VERZONI is associate editor of NFPA Journal. Follow him on Twitter @angelo_verzoni. Top photograph: GETTY IMAGES