What Are Chimney Liners?

A clay, ceramic, or metal conduit installed inside of a chimney, intended to contain the combustion products, direct them to the outside atmosphere, and protect the chimney walls from heat and corrosion.

The installation of a flue liner is highly recommended where any heating appliance is to be installed and flued through a masonary chimney. American tests in the 1980's revealed unlined chimneys to be so unsafe that researchers deemed them to be "little less than criminal".

 

The Primary Functions of Chimney Liners:

 

1) Liners protect the masonry from the corrosive by products of combustion (e.g. soot).

 

2) Liners provide a correctly sized flue for optimum efficiency of appliances. Modern woodburning stoves and gas or oil furnaces require a correctly sized flue to perform properly. The chimney is responsible for not only allowing the products of combustion a passage out of the house, but the draft generated by the chimney also supplies the combustion air to the appliance. An incorrectly sized liner can lead to excessive soot build up in wood-burning stoves, and the production of carbon monoxide with conventional fuels