Creosote, the black or brown residue of combustion that collects about the interior surfaces of a chimney flue liner, is very flammable. If permitted to Develop up, it can capture fire, creating cracks in "fireproof" brick, stone or clay flue liners and allow warmth to reach nearby wood framing and various https://masonry-repair83693.blue-blogs.com/34526728/mantels-fundamentals-explained