What types of liner insulation are there?

There are three choices when it comes to insulating a flexible flue liner.:

Linerthem wraps around the liner, is easy to install and takes up very little room making it suited to confined spaces. It's ideal in situations where you would like to use a pot hanger cowl and can also be used in chimneys with modest bends.

Leca insulation is made of small, light, round pebbles of expanded volcanic rock. Leca is poured around the liner all the way to the top of the chimney. Leca is not suited to very large chimneys / inglenooks, etc but is suited to chimneys that bend. Leca is superior to vermiculite as it does not compress if it gets damp.

Read more about types of liner insulation