Chimney liner insulation is designed specifically for metal chimney liners. Liners help prevent creosote build-up by not allowing the flue gasses to cool down too much. Creosote is highly flammable and is the leading cause of chimney fires. Chimney liner insulation is also a safety issue when relining a chimney for a wood burning stove. It keeps creosote build-up down in the event of a chimney fire. There are two types of ways to insulate your chimney. Thermix insulation is a ready to mix compound that simply mixes with water and pours into the space between the liner and the masonry chimney. A great solution when space is too tight to install a blanket style insulation. Insulation blankets are typically used when there is sufficient space to be installed and also greatly reduce creosote build-up. When you use insulation blankets, the reline job provides a zero clearance and achieves UL1777 rating. Insulation blankets can withstand temperatures up to 2100 degrees F. Lindemann Chimney also sells chimney liner kits good for wood, oil, coal and gas appliances.