False fire-related claims can undermine public confidence in building codes and masonry designs

Words: Bob AbelFire safety is foundational to both masonry construction and all building codes. False marketing claims that negate fire safety have the potential to destroy the public’s trust in both masonry construction and building codes.

In the mid-1990s, two aminoplast masonry foam insulation manufacturers, Tailored Chemical Products Inc. and Thermal Corporation of America Inc., started claiming that by injecting their foam insulation, the fire-resistance rating of CMU walls increased from 2 hours to 4 hours. Both offered abstracts and cover letters of test reports to support the claims. In 2008, cfiFOAM Inc., after reviewing complete copies of the test reports, saw that things did not add up because:

57.14 percent of the test panels’ core cells were filled with grout. The CMU were 100% expanded shale high-performance CMU with equivalent thicknesses well above that needed for calculating 2 hours.
One claimant’s 12-inch CMU wall panel test results were applied to 8-inch CMU walls without further testing.
Another claimant’s Florida installer circulated a recalled 1995 test report despite the testing lab’s instruction not to circulate the 1995 report that the lab recalled due to lab error. The test was repeated in 1996 at the lab’s expense.
A photograph of the test panel in the 1996 test shows snow-white foam behind where the panel’s face wall had spalled off. Aminoplast foam chars above 190Â°F. Furnaces reach 2,000Â°F during 4-hour fire tests.
The P.E. who managed the fire test lab and signed the 1996 test report stated that the “proprietary formulation” of foam used in one claimant’s 1996 test contained a “special ingredient” not found in the client’s standard foam. The “special ingredient” increased the water content of the foam. The water turned to steam and thus kept the panel core below 250Â°F until test termination at 4 hours.

Many local building officials and fire marshals bought into these enhanced fire-resistance rating claims without performing adequate due diligence. Two state fire marshals endorsed one manufacturer’s claim in writing.

In 2000, a New Jersey architect approved a “value engineered” submittal to substitute unlisted 8-inch CMU walls insulated with Core-Fill 500 for more expensive 8-inch CMU walls (UL Design U904) that had been approved for construction by Trenton’s CBO. Discovery of the unlisted walls led the CBO to shut the job down, and require ASTM E 119 testing of a panel built using 8-inch CMU and mortar from the jobsite and insulated by the same installer who had performed the work. The test failed in 1 hour, 58 minutes and 45 seconds, confirming that (1) Core-Fill 500 cannot increase fire-resistance ratings and (2) 8-inch CMU do provide nominal 2-hour protection.

In 2002, the assistant to the Phoenix, Ariz., fire chief wrote regarding the claim made for Core-Fill 500 that foam insulation does not increase fire ratings. In 2009, as Phoenix fire marshal and ICC board member, she confirmed in writing that her opinion had not changed.

The offices of the state fire marshal in both Tennessee and Georgia wrote widely circulated letters endorsing Tailored Chemical Product’s claim that Core-Fill 500 can increase fire ratings of 8- and 12-inch CMU walls from 2 hours to 4 hours.

In 2009, the office of the state fire marshal in Tennessee rendered its 1996 endorsement “null and void.”

In 2011, the Florida Building Commission replaced the state code’s party wall language with base party wall language. Until then, the Florida Building Code required 4-hour party walls; thousands of 8-inch CMU walls were specified and/or detailed by architects to be filled with Core-Fill 500 masonry foam insulation. All were approved for construction by local building officials as 4-hour rated. None will perform as approved. The practice continues. Though the 4-hour party wall language was deleted from the 2010 Florida Building Code, some local Florida jurisdictions apparently retain 4-hour party walls by local amendment.

In 2012, also in Florida, the office of the attorney general investigated Tailored Chemical Products’ and Tailored Foam of Florida’s 4-hour claim.

1n 2013, Tailored Chemical Products deleted the 4-hour claim from their guide specs.

In 2014, Tailored Chemical Products notified Arizona’s Registrar of Contractors that it had withdrawn the increased fire-resistance rating claim. Also in 2014, the Georgia state fire marshal rescinded earlier letters of endorsement dated 1996 and 2004.

Bottom line: Despite Tailored Chemical Products’ having withdrawn the claim, some Core-Fill 500 installer representatives continue making the claim through submittals via masonry contractors to general contractors for architectural approval. Claims that Core-Fill 500 masonry foam insulation can increase the fire rating of any CMU wall are utterly false.

False fire-related claims can undermine public confidence in building codes and masonry designs

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