Flex Liner Installs

Chimney Liner and Flue Liner Installation

Stove installation using flexible stainless steel liner.

Most of our woodburning stove installations involve re-lining the chimney with a flexible stainless steel liner.

Flexible stainless steel liner is passed all the way through the chimney structure from the room to the top of the chimney pot so that it connects flue outlet on the stove directly to the outside world. This method ensures containment of all of the smoke and gasses safely until they discharge to the outside world.

Most people ask us “What’s the difference between 10 year and 25-year liner?"

• There are two grades of stainless steel used to make multifuel liners. 904 and 316 grade
• 904 grade is more resistant to corrosion and usually carries a warranty of 25 years
• 316 is still very robust stuff but only carries a warranty of 10 years

The vast majority of our installations are done using 904-grade stainless steel flexible liner.

There are several good reasons to re-line the chimney.
First and foremost is to be absolutely certain that the flue will work safely. When we re-line an old chimney we know for certain that all of the dangerous gasses associated with burning fuel are contained and won’t leak into the house.

Another reason is the effective and efficient operation of the stove. Stoves are designed to have a smaller throughput of air than open fires and to operate with a specific flue liner diameter. Having a flue liner with a continuous diameter for the full length of the chimney helps the stove to work at its optimum.

Sometimes the old chimney has reached the end of its life. Soot is corrosive to mortar and therefore over time the joints between the bricks break down until the chimney leaks smoke, carbon monoxide, tarry deposits and soot into the house.
Re-lining the old structure means everything is properly contained.

Even fairly new ‘refractory’ chimneys sometimes need to be re-lined as they can be cracked, damaged or even installed incorrectly in the first place. Here you can clearly see the clay liners have cracked apart.

Connecting a stove to a chimney made of bricks (constructed before 1966) means that the tars and creosotes produced by burning wood won’t simply settle and condense on an impervious surface where they can be easily removed. Instead they soak into the surface of the bricks where they will remain until they leech out on the other side.
Most often visible on the outside but it does happen inside too.

This flue liner had been installed into a chimney where a stove had been connected to the open flue for years.
The chimney structure had failed and the householder had a flue built by a local builder.
You can quite clearly see the deposits on the bricks which were difficult or impossible to remove. So the installing builder didn’t bother.
This 1mm stainless steel flue pipe which ought to last 20+ years had corroded through in less than 5 years because it was corroded from the outside by the old chimney deposits.
The only solution was to remove the flue, clean the chimney properly (a 3 hour job in its own right) and re-line with a flex liner in a protective / insulating wrap.