Massachusetts officials say state regulations effectively ban the use of highly flammable material in high rises that is being linked to the rapid spread of a deadly fire at a London apartment tower.
Exterior wall materials used in Massachusetts buildings taller than 40 feet must pass fire-safety testing, in accordance with the state’s building code, officials said. The state code is based on national standards, and regulators in the United States have required such testing since 1998.
“The Massachusetts Board of Building Regulations and Standards takes its responsibility to protect the citizens of the Commonwealth seriously and to ensuring that all buildings are safe and meet the proper building code requirements,” said a statement from Chris Goetcheus, a spokesman for the state’s Division of Professional Licensure.
The state’s building code right now matches the national standards for fire-safety testing of high rises.
State officials are working to update Massachusetts’ building code, and the proposed revisions would allow builders to forgo fire-related testing in some cases that national standards don’t allow for.
However, none of the exceptions would allow for high rises to be built using the type of highly flammable skin, or cladding, found in the 24-story Grenfell Tower where at least 80 people perished June 14.
One of the proposed exceptions to testing in Massachusetts would apply only to buildings shorter than about seven stories (the height cut-off for what regulators consider to be high rises). And it would only exempt those shorter buildings from testing if they are equipped with an automatic sprinkler system throughout that meets a certain set of standards.
The other exception to testing would apply to high rises, as well as some shorter buildings, but only ones with exterior walls constructed of noncombustible materials — such as glass, concrete, or steel. And it would only exempt those buildings from testing if they meet a set of fire-blocking standards.
Fire experts said proposals to amend local building codes in ways that deviate from national standards can raise questions.
“For an organization like us, our antenna [goes] up,” said Robert Solomon, fire protection engineer at the National Fire Protection Association, which sets the standard for testing building materials.
But that doesn’t necessarily mean the proposals would make buildings more dangerous. Local jurisdictions make code amendments all the time for a wide range of reasons.
“This is a proposal that clearly someone has studied and is considered to be an alternative method of protection,” said Rob Neale, vice president for fire service activities at the International Code Council, the organization that oversees national building code standards.
Richard MacKinnon Jr., president of the Professional Fire Fighters of Massachusetts labor union, said he did not think the proposed exceptions would increase the risk of fires spreading more quickly.
“I don’t see it as an issue,” he said by phone.
Experts said there are several reasons why fire-related building code rules are generally less restrictive for shorter buildings than they are for taller buildings and high rises.
For one, the ladders, hoses, and other equipment firefighters use to try to contain fires can reach lower structures more easily. Shorter buildings are also easier to evacuate and tend to hold fewer people.
Cost considerations might also come into play. Testing the flammability of exterior wall materials can be expensive — in the range of $30,000 to $50,000. Though experts said builders don’t have to do the tests as long they use a wall assembly that has passed testing before.
The cladding in London’s Grenfell Tower consisted of two sheets of aluminum that sandwich a combustible core of polyethylene. Solomon of the National Fire Protection Association said the cladding used on the tower was a kind of “metal composite material,” or MCM.
He said use of MCMs for exterior walls has become more common in recent years because they are good at insulating and providing energy efficiency benefits and protecting against rain and moisture. They also can have aesthetic appeal.
But, according to experts, no aluminum cladding made with pure polyethylene has ever passed the testing required for construction of taller buildings in the United States. As a result, US building codes have effectively banned such flammable cladding in high-rises for nearly two decades.
“In the US, once the building gets into that high-rise category of a building, the regulations get much more conservative and restrictive,” Solomon said.
In Britain, fire safety tests of at least 600 high-rises were ordered after the fire at Grenfell Tower.