Chimney Liners

The Key to a Safe Home and Long Lasting Chimney

1. First, what is a chimney liner?

A chimney liner lines the inside of your chimney and are made of either clay, ceramic, or metal.

2. What is the purpose of a chimney liner?

Maintaining your chimney liner is imperative to keeping heat from escaping through your chimney, keeping carbon monoxide out of your home, and extending the life of your chimney.

All of the smoke and gasses created in your fireplace travel out through the liner. When you burn anything – whether in your fireplace or anywhere else, dangerous by-products are created.

In the case of your fireplace, the main by-product is carbon monoxide. Your chimney’s liner serves a vital purpose – to contain the carbon monoxide and direct it outside.

Additionally, the liner serves to protect your chimney’s walls from heat and corrosion. An old or broken liner could put your chimney at risk for corrosion and allow carbon monoxide to enter your home.

3. Why do I need a new liner?

  • You may not have a chimney liner at all. If your home was built before 1940, it may have been built without one.
  • Your existing liner is damaged.
  • You are installing a new heating unit (stove, furnace, etc.) which needs to be vented.

4. How do I know there’s a problem?

The best way to know is to have your chimney cleaned and inspected annually by a licensed chimney professional.

Additionally, you can look inside your chimney for:

  • Excessive buildup on the inside of the chimney
  • Cracks in the flue tiles
  • Damaged or missing flue tiles
  • Missing mortar in the flue tiles


Types of Liners

If you do have a liner it will be one of three types:

1. Clay Tile Liner

Some houses were built with a clay tile liner, generally, these are not put in post construction as they are difficult and expensive to install.

1. Tiles themselves are inexpensive
2. Withstand very high temperatures
3. Stand up well against corrosive materials in fireplace
4. Last about 50 years

1. Post construction installation is very difficult and costly
2. Repairs and replacements are very difficult and costly
3. Air can get caught between tiles causing draft
4. Tiles can break

2. Cast In Place Liner

If your chimney is in rough shape, this liner can help stabilize and reinforce it while also giving you the benefits of a liner.

Basically, a mortar is pumped into the chimney, creating a liner. The specific mortar mix and method for installing varies, but the overall technique is that the mortar is poured and held in place with a bladder which is then removed once it hardens.

They provide great insulation and can allow greater temperatures to be reached which allows for cleaner fires and less creosote buildup. Like the Clay Tile Liner, these can last up to 50 years.

3. Metal Flue Liner

A common and the simplest fix for a chimney with a missing or damaged liner is the metal flue liner. It may be rigid or flexible depending on the needs of your chimney (chimneys with bends and curves require flexible). They are typically made using a stainless steel alloy and work well to remove by-product from the fireplace. An insulation may be added to the liner if there is a need to hold in more heat and prevent condensation. Ask your professional if they are insulating the liner and why or why not.

These come in various weights and prices vary depending on the need. They can be Heavy, High Performace Light and Light. Ask your chimney professional which type they are installing and why.

Your liner should come with a lifetime warranty – check with your chimney professional to assure yours does.