What is the minimum inches a hearth extension must be if the masonry fireplace opening is less than 6 square feet?

The correct answer is based on the guidelines set forth in safety and building codes related to masonry fireplaces. For a fireplace opening that measures less than 6 square feet, the minimum required hearth extension is typically established at a distance of 16 inches. This dimension serves a critical purpose in enhancing fire safety by providing a barrier to catch embers and direct heat away from combustible flooring materials. Adequate hearth extension helps to mitigate the risk of fire hazards that may arise from logs rolling out or embers escaping during the use of the fireplace.

If a hearth extension were inadequate—such as being only 10, 12, or 14 inches—it would not offer the same level of protection, potentially allowing for increased risks of fire spreading to surrounding areas or combustibles near the fireplace. Therefore, adhering to the specified minimum of 16 inches aligns with safety standards intended to ensure proper containment of heat and embers.