Chimney liners are conduits made of clay, metal or ceramic material that are installed inside chimneys with three main objectives; to contain combustion products, to safely guide them outside and also to protect walls of chimneys against corrosion and heat.

Even though building regulations may differ, installation of chimney liners has been strongly recommended since the beginning of the 21st Century. As a matter of fact, most fire regulations make it mandatory to install flue lining.