This HeatShield Cerfractory Foam is an insulating, high-temperature refractory mortar, developed specifically for spray coating smoke chamber walls. When properly applied, it will restore the integrity of your fireplace. This product will insulate, seal gaps, and smooth the smoke chamber walls as required by both NFPA and IRC codes. HeatShield Cerfractory Foam Smoke Chamber Sealant helps to ensure the safe and efficient operation of your fireplace. Your masonry fireplace has an area called the smoke chamber. In most fireplaces it can be easily viewed by shining a strong light up through the damper. Its function is to safely transition smoke and hot gases from your fireplace to the narrow flue of your chimney. Roughly the shape of an upside down funnel, the smoke chamber starts just above the damper and ends where the chimney begins. The bricks along the sides of the smoke chamber are often stepped outward, one above the other, until they meet the flue. This is a process called "corbelling". The corbelled brick in your smoke chamber will look like an upside down staircase. To protect the integrity and efficiency of your fireplace, the smoke chamber should be free of any gaps, cracks, or jagged edges. The corbelled areas of the smoke chamber should be coated with an insulating, high-temperature mortar to fill any gaps and to smooth out any jagged edges. According to the National Fire Protection Association (NFPA), defective smoke chambers are the third leading cause of chimney-related house fires. For the safety and efficiency of your fireplace, it is important that any gaps, cracks, or holes in the smoke chamber be sealed and the brick corbelling be made smooth. Because the smoke chamber is a high heat area, any gaps, cracks, or holes can allow excessive heat to attack any surrounding wood or combustibles. The jagged corbelling slows the draft and will provide more surface area for highly combustible creosote and soot to form.
WARNING: Carcinogens: This product can expose you to chemicals including Lead, which is [are] known to the State of California to cause cancer. For more information go to www.P65Warnings.ca.gov.