Block and Clay flue Gap
by Michael Boutin
I am building a chimney and I am using 8x8 chimney blocks and 8x8 clay liners. There is a 1 inch gap between the two and I would like to know what is the best way to stabilize the liner inside the blocks. I have heard to fill the gap in with ruble (whatever that is) or some sort of RAW insulation. I want to make sure this is correct so what is your suggestion.