If you want to make sure that your chimney not only has a longer lifespan but also ensures you’re getting the maximum benefits from it, a chimney liner is an essential component of every chimney (notwithstanding helping in eliminating health dangers too).

 

Your chimney liner aids in directing combustion by-products away from the chimney itself in fireplaces and stoves that burn oil, gas or solid fuels.

 

The region inside your chimney where smoke and gases from your fireplace or other heat-producing appliances such as stoves are directed and properly vented outside your home is called the flue, and it is covered by a single chimney liner or a series of interlocking flue liners.  Clay, stainless steel, or pumice are just a few examples of the various materials used to make chimney liners. 

 

Every material has a function, yet depending on that purpose, certain materials will differ from others. Which liner you should place also relies on the kind of chimney you have and the outcomes you anticipate.

 

Smoke can securely and effectively exit your property through a clean, direct route made possible by chimney liners. Without one, the chimney’s walls will ultimately decay, and any gaps will allow smoke to penetrate. The likelihood of a chimney fire increases significantly when smoke cannot be released from your chimney efficiently outside. The chimney liner is just one of the numerous chimney components that keep your chimney operating securely and efficiently.

 

Some valid reasons why you need a chimney liner to include:

 

Safety

For a little investment, a chimney liner will make your home safer. Cracked clay flue liners or missing infill in an old chimney can let dangerous gases and smoke into your living spaces, bedrooms, attic, or ceiling, endangering you and your family. Leaks are reduced with chimney liners.

 

A high-quality chimney liner will shield your chimney from harmful fire by-products as well. To ensure that smoke, creosote, and carbon dioxide from burning fuels are vented outside without coming into contact with the actual chimney structure, the liner is a sealed unit from bottom to top.

 

A correctly installed liner with the right diameter will help mitigate any CO2 spilling from the stove/fireplace into the room. We recommend the use of a CO2 monitor which should be installed with any heat-producing appliance. In addition, Irish building regulations deem it necessary the installation of an outside wall vent.

 

Protection

In order to stop excessive creosote or condensation from building up inside your chimney, you can insulate the chimney liner. Granular or wrapped insulation can be applied to liners either before or after installation. This insulation fills the gap between the flue liners and the chimney shaft. Additionally, when the fire is not in use, an insulated flue will remain warmer than one without and should help stop cold air from sinking down the chimney. However, to completely prevent cold air from sinking down the chimney when the chimney has gone cold, the homeowner may need to mechanically induce the draft with an electrical cowl.

 

A stainless steel flexible liner can help prevent condensate from occurring in a chimney because a smooth stainless steel liner can help to quickly vent hot gases and smoke before they have a chance to turn into moisture droplets as opposed to the rougher and less smooth walls of a clay chimney liner.

 

Improves the lifespan of the chimney

A chimney liner shields the masonry and joints of the chimney shaft from the heat of the fire. In addition, it shields the chimney from potential corrosion caused by the fire’s acidic flue gases.  Without a liner, the chimney shaft is always exposed to the gases, heat and smoke produced by the fire. These elements damage the chimney’s structure over time. Smoke leaks, an increased risk of fire and the risk of collapse could all come from a disintegrating chimney.

 

Ensures appliance efficiency

It is crucial to confirm that the chimney flue is the size advised by the stove manufacturer when households have a new fuel heat-producing appliance installed. The appliance will run as efficiently as possible by ensuring the correct diameter liner is installed. When the liner is the wrong size, the chimney draft is typically insufficient, and excessive creosote accumulation happens in the flue with multi-fuel appliances, necessitating more regular chimney liner cleaning.

 

Why Should You Insulate Your Chimney Flue?

There is no question that an insulated flue liner improves the performance and draught of your masonry chimney compared to one without one, but why insulate your chimney flue?

 

Your chimney liner should be insulated primarily to ensure that it warms up more quickly than one that isn’t. This means less heat loss from the exposed metal liner inside the masonry chimney

 

Flue gases inside the flue rise faster and stay warmer for longer when the flue liner is warmer; this helps the fuel in your stove burn more efficiently, which gives you more heat in the room.

 

Having a chimney that draughts properly will mean:

 

• Less sooty or creosote deposits building up on the flue’s interior walls could catch fire and start a chimney fire.
• Fewer potentially harmful particle pollutants are emitted into the atmosphere.
• It will be less likely for the wind to blow fumes and gases from the stove or fireplace into the chimney, creating a downdraught.
• After the stove or fireplace is out, the chimney will be less prone to experience cold air seeping down through it.
• It is unlikely that the chimney will experience a lack of draught when the combustion products draught correctly upwards.

 

When Is It Required To Insulate A Chimney?

The short answer is ALWAYS. But with the examples below, insulating a chimney will help improve draught

 

There will be a significant cold air space surrounding the flue housed in the masonry chimney if the chimney shaft is extremely wide. If not insulated, this cold space will absorb heat from the flue liner, which could lead to an improper chimney draught.

 

It is also crucial to insulate the flue if the chimney breast protrudes from the wall and is surrounded by cold, outside air on three or more sides, or if the flue is contained within a lengthy, free-standing chimney stack that is encircled by cold air on four sides.

 

Lastly, you might need to insulate the chimney if it is too small. It is recommended to help enhance the length of shorter chimneys since they do not draught as well as longer chimneys.

 

What Kind Of Insulation Can Be Used For A Flue?

A flexible flue liner that is wrapped in an insulating blanket or wrap, such as SHL’s AGC Thermal Wrap, during installation.

 

Vermiculite or perlite granules are mixed and put around the flue liner, however old chimneys that may have holes or have grown porous should be avoided since the granules could leak into another flue or into another area of the house.

 

After you’ve installed and insulated your flexible liner, it’s always advised to attach a cowl to the top of the chimney. Read more about our selection of chimney cowls here. Some chimney cowls are known to improve draught.