A flue liner is required by codes and standards to cover the inner surface of the flue of your chimney. Relining a chimney is a procedure during which damaged or deteriorated liners are removed and and better, safer systems are replaced. There is a great variety of materials comprising these liners including, but not limited to, ceramic tiles, firebrick, stainless steel, cast-in-place masonry mixtures, or listed lining systems of similar materials. Flue liners for residential and low heat chimneys must be separated from the chimney wall by an air space to protect the life of each separate flue system. Flue liner tiles can crack due to rapid heating of a cold flue or abusive maintenance, as well as damage from a chimney fire. A cracked liner tile is not safe and must be replaced before burning further.
Faulty appliances are actually the cause of a slim percentage of chimney fires. Rather, the major causes are either improper installation or a poorly maintained flue system. Deteriorating liners may be allowing smoke or creosote to seep through the liner into the walls of your chimney. Relining your chimney will actually prevent excessive creosote buildup when venting a wood burning fireplace or stove.
When a chimney fire has occurred or a tile is cracked by some other means, there are many different directions a homeowner can take to
reline the chimney. Stainless steel liners, whether rigid or flexible, are excellent options. Rigid liners are made of nonmagnetic stainless steel and come in round tubes five to ten inches in diameter and one to four feet long. Flexible stainless steel liners are much thinner and are of ribbed construction. The flexible liners are easier to install but the rigid liners are more efficient due to their smooth walls.
Aluminum liners are designated to line very specific types of gas-fired systems, but not gas fireplace logs. Chimney caps are recommended for any type of liner, whether tile or metal, and proper insulation should be installed.
A cast-in-place liner mixture requires the careful installation of exactly proportioned, inflated, round or oval bladders and casting a masonry material around them. Older or particularly weak chimneys can benefit most from this style of flue lining because, after curing, this masonry material greatly increases the strength of the chimney.
Occasionally a homeowner may come across a situation where a company gives a choice of a full reline or a reline going about six feet up the chimney. A few reasons why you should choose the full reline would be that with the six foot liner, your appliance or fireplace is guaranteed to operate at less than 100% efficiency. Also, the heavy liner will have to be removed for every cleaning which requires more effort and therefore more money.
It is absolutely imperative that you do not burn a fireplace if there is a cracked flue tile. Contact local chimney repair companies or visit amchimney.com for more information and answers to specific questions regarding your unique chimney. Once flames move through the cracked or deteriorating liner, there is no stopping them from lighting the entire rest of the chimney and roof aflame. Allow the experts at amchimney.com to answer all your questions!