What is the minimum thickness for a concrete foundation for a masonry fireplace?

The minimum thickness for a concrete foundation for a masonry fireplace is 12 inches. This requirement is in place to ensure that the foundation provides adequate support and stability for the heavy structure of the fireplace. A thicker foundation is necessary to distribute the weight of the masonry and to resist any cracking or settling that could occur over time. The thickness helps to absorb the thermal expansion and contraction effects that fireplaces may experience due to the heat generated during use. Ensuring the correct thickness is essential for the safety and longevity of the fireplace installation, as a foundation that is too thin may lead to structural failures or compromises in performance.