Fire Protection

Firing Clay Brick

The primary ingredient in brick is clay which is fired to around 2000 F, which is why brick is classified as a non-combustible material. Moreover, both the National Institute of Standards and Technology and BIA conducted separate fire tests that conclusively demonstrate that nothing outperforms good old-fashioned brick in a one-hour fire test. Vinyl and fiber cement? Well, even though brick is now used as a veneer application rather than carry structural loads, the results confirm why fireplaces are typically made of brick and not other materials.

BIA Tests Confirm Brick’s Superiority

Hollow Brick Fire Testing. In 2009, BIA conducted fire tests at the Southwest Research Institute in San Antonio in accordance with ASTM E 119, the Standard Test Method for Fire Tests of Building Construction and Materials. A new, “hollow brick” product was tested along with vinyl siding and fiber cement in typically constructed exterior wall sections.  Each material was subjected to fire for one hour or until one of the failure criteria was met (wall collapses, flame or hot gas penetrates the wall, or when the temperature rises to 250°F or greater on the unexposed (interior) side of the wall.)  No one was surprised when vinyl failed in under 20 minutes.  Surprisingly, fiber cement couldn’t attain one hour.  Needless to say, the brick passed easily.

While it’s no surprise that vinyl siding becomes engulfed in flames pretty quickly, fiber cement does not attain a one-hour fire rating like brick

Thin Brick Fire Testing. In late 2018, BIA conducted fire tests at the Intertek Building & Construction facility in York, Pennsylvania in accordance with ASTM E119, Test Methods for Fire Tests of Building Construction and Materials, and NFPA 285, Test Method for Evaluation of Fire Propagation Characteristics of Exterior Non-Loadbearing Wall Assemblies Containing Combustible Components. 

The specific wall assembly tested utilized thin brick veneer adhered to cement board with a thin layer of polymer modified mortar (thin set).  Behind the cement board, a drainage mat, extruded polystyrene foam insulation, and a fluid-applied water-resistive and air barrier were installed, with the entire system fastened to cold-formed steel framing. Gypsum board was attached on each side of the steel framing and fiberglass batt insulation was installed between the studs. 

As indicated in the BIA Thin Brick Fire Test Summary Reports below, the tests demonstrated that the thin set thin brick veneer wall assembly provides a one-hour fire resistance rating on both the exterior and interior sides of the wall and meets code-mandated limits on fire propagation to combustible components within the wall. In addition, based on the post-test inspection results, below you will find the Engineering Analysis Report written by Jensen Hughes, a qualified, recognized fire safety engineering consultant. The report lists and justifies alternate materials which are permitted to be substituted for specific components within the tested wall assembly. The report also justifies that a thick set thin brick veneer wall assembly will provide the same or better fire resistance and flame spread propagation performance as the wall system tested at Intertek in accordance with ASTM E119 and NFPA 285 respectively. The above reports are often cited by local building code officials as substantiation for the use of thin brick wall assemblies in buildings to provide the appropriate level of fire resistance and to limit fire propagation.

Real World Scenarios

         See how the proliferation of these lightweight materials affect
                                    fire story from this story in 2017


The International Building Code (IBC) acknowledges that clay brick typically used for residential construction provides at least a one-hour fire resistance rating. In fact, President George Washington recommended brick or stone requirements for party wall construction in the capital city's row houses almost 220 years ago because of concerns for fire safety. Several American cities such as Baltimore, Chicago, Denver, Portland, Maine, and St. Louis, adopted the wide usage of brick - and often mandated its use in local building codes - in the aftermath of devastating fires. 

With proliferation of synthetic, lightweight materials, vinyl siding, fiber cement, EIFS and even manufactured stone need other elements in the wall assembly to attain a one hour fire rating.  Brick doesn’t.

Fire Professionals Agree

Retired fire chief, Gary Bowker showed a test that demonstrates the speed at which a fire can move from ground level up into the attic of homes.  Check out this article and video that he put together and see for yourself what he has to say.