Chamber Safe is a high performance, refractory parging material, designed to strengthen, streamline, and restore the critical smoke chamber area in masonry chimneys. Preferred by chimney professionals, Chamber Safe smooths jagged, corbelled walls typically found in the smoke chamber, and creates a smooth transition between the smoke chamber and flue liner. A smooth transition into the flue typically improves the flow or draft of the fireplace. The unique insulating properties of Chamber Safe material improves the safety of the chimney by reducing radiant heat transfer through the smoke chamber. This product is non water soluble.