Probably the most essential fireplace accessory that will keep your home and family safe is a chimney liner. Extreme temperatures and toxic gases are produced when you light a fire in a gas or wood burning fireplace. These combustion products are capable of causing damage to your fireplace, chimney and home, and can even make you sick.

A chimney liner is an insert made from materials such as metal, clay or ceramic that keeps your chimney safe from these combustion byproducts. It also protects the chimney walls from heat and corrosion. Once the chimney gets overheated or sustains some damage, any nearby wood used in the construction of your home is at risk of catching fire.

Testing has revealed that unlined chimneys are very hazardous. In the US, homes containing a fireplace that were built after 1940 must have a chimney liner, and they must be replaced if broken or cracked.

Chimney liners come in three main types:

1. The traditional material for chimney liners is clay tiles. This is an inexpensive option, easily obtainable, and works satisfactorily in an open fireplace chimney that is suitably kept up.

2. Metal chimney liners, typically made from stainless steel or aluminum, are generally utilized for upgrade or repair to an existing chimney. Metal liners enjoy a good safety rating and are tough and long wearing if installed properly.

3. Then there's the cast-in-place liner. This is a lightweight product made from a material resembling cement. Once installed inside the chimney, it forms a well insulated, seamless passage to allow the combustion byproducts to escape. This permanent liner can enhance the structural integrity of an older chimney, and is suitable for all kinds of fuel.

The material of choice for most replacement chimney liners these days is stainless steel rather than clay tiles, because it's a more efficient installation process. You can get it in either stiff or flexible varieties.

Generally, homeowners will want to have a chimney liner installed by professionals. But you can save some money by purchasing a kit which comes complete with detailed installation instructions. The kits usually include all the required accessories and attachments to get the job done.

If your house has a working fireplace, it's highly important that you get a professional inspection to ensure that it meets today's safety criteria, particularly if it's an older home. If you have an old chimney that's in poor repair or not properly lined, you're putting your family's safety at risk. And because there is no shortage of inexpensive and practical ways to fix the problem, you have no reason to shy away from this highly important fireplace accessory.