Duravent kits are designed to stay cool on the outside, to provide a hot draft on the inside, to boost stove efficiency, and to provide for a fire-safe design that protects both the chimney and the building. This triple-wall chimney features two insulating layers (ceramic blanket, plus air space). The ceramic blanket insulation is held securely in position, eliminating hot spots common with loose-fill type insulations. In the event of a creosote fire, the compressible blanket insulation permits the chimney liner to expand outwardly in a radial direction. Duravent chimney is a triple-wall, all-fuel chimney for use with wood stoves, fireplaces, furnaces, boilers, stoves, ranges, water heaters, or other appliances fueled by wood, oil, coal, or gas.