Santa's Friend Chimney Service

The Different Types of Chimney Liners

A masonry chimney is lined with a ceramic, clay, or metal conduit that contains the products of combustion, directs these outside the home, and protects the walls of the chimney from corrosion and heat. Most fire codes mandate use of a chimney liner due to the safety hazards presented by an unlined chimney. The National Bureau of Standards found that heat moves through an unlined chimney so quickly that adjacent woodwork may catch fire within just 3 ½ hours.

The different types of chimney liners

Chimney liners protect homes from heat transferred to combustible materials during fireplace use. Liners also protect chimney masonry from corrosive byproducts of combustion that can reduce chimney life and threaten home occupant safety. The three main types of chimney liners are: metal, clay tiles, and cast-in-place.

Metal liners are made from aluminum or stainless steel and typically used to repair or upgrade an existing chimney. Aluminum is used for a medium efficiency gas system while stainless steel is appropriate for gas, oil, or wood burning systems. High-temperature insulation is installed with this liner to improve performance and safety.

Clay tile is the most common type of chimney liner. It is inexpensive, easy to obtain, and performs well in an open chimney system. However, it does not rapidly absorb or evenly distribute heat during a chimney fire. Unequal expansion may cause flue tiles to crack or split. Clay tiles cannot contain liquid byproducts of combustion from modern gas systems.

A cast-in-place chimney liner is a lightweight, cement-type product. It is castable and installed inside a chimney to provide flue gases with a seamless, insulated passageway. This permanent liner can improve the structural integrity of an aging chimney. Homeowners should have a chimney inspection to determine whether a new metal, clay tile, or cast-in-place liner is required to bring the system into compliance with current fire and safety codes.