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Flammable cladding in Grenfell Tower disaster found on buildings far and wide

 

 

 

 

 

 

 

 

 

 

For decades, architects and developers have put cheap, highly flammable wall panels on the exteriors of multi-storey buildings.

A four-storey drug and alcohol treatment centre in Atlanta has them. So does a six-storey building at California State University. The panels might be on a 15-floor federal courthouse in Florida and a 33-storey Marriott hotel in Baltimore. They apparently cover a front wall and line the dining hall at Clayton State University's main building.

The glimmering panels can give an aging edifice a space-age lustre. They help with insulation. And they save money. But sandwiched inside them, between two thin sheets of aluminum, is a layer of polyethylene, the same common plastic that burned hot enough in March to destroy a section of Atlanta's Interstate 85.

In the aftermath of London's Grenfell Tower disaster, in which metal composite panels with polyethylene have been blamed for a deadly inferno that roared up a high-rise public housing building, fire experts around the world are questioning if the materials should be used at all.

A Grenfell Tower apartment after fire engulfed the building within 15 minutes. 'It was like a tissue being set alight,' ...

A Grenfell Tower apartment after fire engulfed the building within 15 minutes. 'It was like a tissue being set alight,' said one witness. Met/AP

And pointed questions about which US buildings wear the panels have gone unanswered, thanks to shoddy record-keeping by government inspectors and building owners alike. It can be nearly impossible to find out if the shine on your building comes from flammable or non-flammable panelling, a review of structures across the country by The Atlanta Journal-Constitution found.

While the polyethylene cladding generally isn't permitted on buildings taller than 12 metres – the reach of a fire truck ladder – local codes have exceptions that can allow the material to go much, much higher, the AJC found.

Standards based on reasonable risk

Should we worry?

"That's a fair question, and that's the question nobody likes to answer," said Robert Neale, who heads fire services for the International Code Council, which develops model building and fire regulations used across the US. "Building codes are consensus documents from all interests in the sector – building officials, fire officials, contractors, developers, architects, engineers ... The standards that we have are based on reasonable risk."

An air gap between the cladding and insulation created a chimney effect at Grenfell Tower, spreading flames faster and ...

An air gap between the cladding and insulation created a chimney effect at Grenfell Tower, spreading flames faster and burning the 24-storey building from the outside in. Frank Augstein

Should we ban it?

The London inferno, which killed at least 80 people, followed a succession of facade fires over the past decade across Europe, the Middle East and Asia. A casino hotel in Atlantic City went up in flames in 2007 while still under construction.

Still, manufacturers continued to sell their product to developers and refurbishers of multi-storey projects. Arconic, the company that supplied the material for Grenfell, warned in some brochures against using polyethylene in taller buildings because of the fire risk, yet in other promotional materials showcased high-rises it said sported the panels.

Arconic now faces a class-action lawsuit from its stockholders, which a company statement described as "meritless", calling such securities cases "a predictable follow-on from tragedies like this". The investors allege the company knowingly marketed the material in Europe and elsewhere for inappropriate uses.

Berlin's fire chief has said he'll ask German lawmakers to bar the material. United Arab Emirates took that step early this year after a series of fires there involving cladding on high-rises.

"Everybody wants to make it look nice, and having the shiny walls that reflect light and give you this kind of effect and all of that," said Albert Moussa, president of BlazeTech Corp, an engineering consulting firm in Massachusetts. "My answer is, you shouldn't. Indeed, you ought to be very careful because of this potential fire hazard."

Banning polyethylene, or PE, cladding would force contractors to spend more on fire-retardant panels, which have a mineral core. British media have reported that by downgrading from zinc to polyethylene, the housing authority that refurbished Grenfell Tower saved the equivalent of about $US380,000 on an $US11 million project.

"Sometimes I wonder if the fire retardant is good enough," Moussa said. "But people go for the cheap stuff, and that's what you get."

Testing high-rise cladding

While the British government has been testing cladding on high-rises since the disaster, with materials on more than 180 buildings already failing fire safety tests, no such initiative has been launched in the US.

Arconic has a manufacturing plant in Eastman. But the Grenfell panels, a product called Reynobond PE, weren't made in Georgia, the company says. Arconic has another plant in France that also makes the panels.

The company announced 12 days after the London fire that it would stop selling PE cladding for high-rise construction because it can't control how the product is ultimately used. Also thought to have contributed to the London tragedy was a layer of synthetic insulation between the cladding and the exterior walls, which gave off toxic cyanide fumes. And an air gap between the cladding and the insulation created a chimney effect, spreading the flames faster and burning the 24-storey building from the outside in.

The tower also lacked a sprinkler system.

The fire started with a faulty refrigerator. Parents threw children out of windows. People on fire jumped to their deaths. Doomed residents on upper floors waved flashlights and cell phone lights, beckoning for help.

After Arconic's announcement, the AJC spent weeks probing use of PE cladding on American buildings.

The review found that even when the material was used higher than 12 metres, that's not necessarily a building code violation. Rules vary based on building specifications and how the panels are installed.

The International Building Code, which many US jurisdictions incorporate, currently allows panels as high as 15 or 23 metres if they can survive heat testing. Most PE products can't.

A 2012 code revision removed height limits entirely if a building has a full automatic sprinkler system, if the metal materials pass heat tests and take up a limited portion of each storey, and if no other buildings sit in close proximity.

But then, local jurisdictions can set their own rules.

'Playing roulette'

Douglas Evans, a Las Vegas fire protection engineer who has been studying facade fires for 25 years, said he has no evidence that the US codes haven't been working.

"But you're still playing roulette," Evans said of allowing the material on buildings with sprinkler systems. "And at some point, you're going to have to pay."

If a facade fire starts on the outside, such as by a dumpster or car fire, internal sprinklers won't do much good, Evans said. If occupants retreat into the safety of stairwells, their pressurisation systems could be drawing in contaminated air. And if people run outside, they'll run out into falling globs of burning debris.

"My understanding is when that's burning and it hits you, it'll stick to you," Evans said.

In many cases where PE cladding was used, the AJC found, it seems no one ever informed the buildings' owners, much less the people who work, live or sleep there.

There are no state or national databases the public can access. City inspection records often don't reveal whether a contractor used cladding with a plastic core or a fire-retardant alternative. Several building managers, contractors and architects contacted by the AJC said they don't know what's in the panels, or sidestepped the question.

Eyeballing the panelling is of no help.

"One of the problems I've had with them is that the fire retardant and the non-fire retardant treated ones sort of look the same," Glenn Corbett, an associate professor of fire science at John Jay College of Criminal Justice, said. "I don't know how you would determine the difference just by looking at them, unless you were there when they were actually being installed."

Destination often unknown

The AJC sought help from companies that make the panelling, to no avail. Arconic CEO David Hess said in second quarter earnings conference call late last month that "more often than not, we don't know where that material is headed when it's sold."

However, before the tragedy Arconic's website touted a list of buildings that purportedly used their PE products, as did many other panel manufacturers.

Another metals material company, Alpolic, says on its website that the Centre for Health and Rehabilitation, a substance abuse and mental health treatment centre in Atlanta, used its PE panelling. For weeks, Fulton County officials couldn't confirm that, and county building records didn't have the answer, either.

Then Joseph Davis, a deputy director with the county's Real Estate and Asset Management Department, dug deeper and confirmed the product is the same type used on Grenfell Tower. The metal panelling was added during a 2005 renovation. It's on the front trim between rows of windows and on a canopy over the front entrance.

Davis said he's not concerned, though, about a fire hazard on the four-storey, 1950s-era building.

"The building in Great Britain was not sprinklered, whereas ours is," Davis said. "The exterior envelope is a brick veneer over poured concrete. That won't burn."

Another company, 3A Composites, maker of Alucobond panels, says on its website that the 15-storey federal courthouse in Jacksonville, Florida, has about 8083 square metres of exterior aluminum composite panels "thermobonded to a plastic core" on its outer trim, parapets and rooftop fins. The federal government, though, says it can't say for sure what kind of metal panels they are and has no plans to replace them.

A spokeswoman noted the building is made of structural steel and steel-reinforced concrete, with multiple stairwells and a sprinkler system.

The website for 3A Composites says the Georgia Aquarium used a combination of the company's fire-retardant Alucobond Plus along with panels "thermobonded to a plastic core". But the aquarium's projects director, Michael Lewis, said polyethylene panels weren't used.

Arconic's website says Cal State's chancellor's office building in Long Beach, built in 1998, has 4645 square metres of Reynobond PE, which "helped deflect the harsh California sun".

The university isn't disputing that. Spokesman Mike Uhlenkamp said the building has multiple exits and 24-hour security.

"Our folks are not concerned for a variety of reasons," Uhlenkamp said. "I think the first being, it's a fully automated, sprinklered building. I think when the building was built, apparently this would have been the standard, so the fire marshal would have inspected these things."

Uncertainty remains

In other cases, what's on the outside of high-rises remains uncertain.

An article on a metal construction industry website says a seven-storey clinic at the University of Texas Southwestern Medical Centre in Dallas has about 2788 square metres of Reynobond's polyethylene core panels. Architects chose it, the article says, "because of the modern aesthetic it projects – the flatness and crispness of the material".

But a university spokesman said in emails that "under fire code at the time of the Outpatient Building construction, Reynobond PE would not have been allowed due to its flammability" and "they were not the same panels used in the building damaged in the London fire."

Clayton State University's four-storey main building, outside Atlanta, has Reynobond on its lower levels, including a front wall over the president's office and on the fascia over the rounded atrium that forms its nucleus.

Arconic's website doesn't say whether it's the polyethylene type, but Harun Biswas, of the school's Facilities Management department, said he spoke with the architect and believes it is PE.

The cladding doesn't appear to surpass 12 metres, and the 13-year-old building has a sprinkler system, fire and smoke alarms. But Biswas said he will consult with the state Board of Regents and the Financing and Investment Commission on whether the cladding should be tested.

"We have to know what that is," Biswas said. "When it comes to fire safety, we don't compromise."

Testing means stripping off a section and sending it to a lab. It's come down to that for owners of the Baltimore Marriott Waterfront, who are awaiting test results after The Wall Street Journal and the Associated Press published stories, based on Arconic's web materials, about the possibility the hotel has the same cladding as Grenfell Tower.

The AP also raised questions about material wrapping the Cleveland Browns' football stadium, as well as the top two floors of a nine-storey office and retail building in Denver.

"I think what this calls out for is some specific kind of labelling on the panels themselves," Corbett, the John Jay College associate professor, said. "If you're an employee in a building like that, you want to know. Joe Building Occupant is not going to know."

Fast-burning substance

There's a reason why PE building cladding is so cheap. PE stands for polyethylene, the most common plastic, used in grocery bags, water bottles, children's toys and – unfortunately for Atlanta – in tubing around fibre optic cable.

For years, the Georgia Department of Transportation stored spools of the high-density plastic piping under an I-85 overpass in the Buckhead neighbourhood. In March, police allege, a homeless man set fire to a chair, which ignited the cable, which set off a roaring blaze that caused a section of highway to collapse in a ball of flames and smoke. An estimated 250,000 drivers had to alter their daily commutes, creating a six-week traffic nightmare until the bridge was fixed.

Polyethylene is mainly made from petroleum or natural gas. It's flammable, but not combustible, which means it can't catch fire on its own. But if it does, watch out – it can burn as fast as gasoline.

The I-85 fire was so large and intense, it chewed through the concrete bridge and its steel beams.

Witnesses told British media that London's Grenfell Tower, which was covered in building cladding with a polyethylene core, became fully engulfed within 15 minutes. "It was like a tissue being set alight," one woman told the Daily Mail.

by Johnny Edwards

Source: http://www.afr.com/real-estate/flammable-cladding-used-on-buildings-far-and-wide-20170808-gxri8q


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