Fire Resistant

Giving your family more time for a safe exit
Fire Resistant

Nu-Wool Premium Cellulose Insulation is one of the few construction materials used in houses that is treated for fire resistance.  Because of its fire resistance, Nu-Wool Premium Cellulose Insulation stops or slows the spread of fire in attics and wall cavities.  Plus, the fire retardants used in Nu-Wool insulation products last the life of the structure.

Firewall Tests

As our firewall test results demonstrate, the dense structure of Nu-Wool Premium Cellulose Insulation and its fire retardants slow the spread of fire through a building by blocking flames and hot gases and restricting the availability of oxygen in insulated walls and ceilings. Scientists at the National Research Council Canada report that "cellulose in the wall cavity provided an increase in the fire resistance performance of 22% to 55%."[1]  The NRCC study showed that "the fire resistance of an assembly with glass fiber insulation was slightly lower than that of a non-insulated assembly."

Furnace temperatures in excess of 1800 degrees Maximum average temperature of unexposed surface: 138 degrees
Furnace temperatures in excess of 1800 degrees Maximum average temperature of unexposed surface: 138 degrees
Exposed surface after removal from furnace End of hose stream test –  unexposed surface still intact
Exposed surface after removal from furnace End of hose stream test – unexposed surface still intact

Fire Retardant Permanency

Fire retardants used in Nu-Wool Premium Cellulose Insulation do not lose their effectiveness over time. Tests by scientists and technicians at Oak Ridge National Laboratory, Tennessee Technological University, Allied Signal corp., US Borax Corp., Underwriters Laboratories, and United States Testing Company, found no sign of "disappearing fire retardant."


NRC-CNRC Report A-4057.2, Results of Fire Resistance Tests on Small-Scale, Insulated and Non-Insulated, Gypsum Board Protected Wall Assemblies, July 1994.