Question: I am buying a Vermont Castings Encore model. It shall be installed in a fireplace on an outside wall with a 10" x 10" square tile flue. Is it OK to just run the flex pipe from the stove into this chimney or should I use a stove pipe liner all the way up the chimney? If I use a stove pipe I will probably go to the 6" reducer. Can I use galvanized 6" pipe from the hardware as this installation is only for a couple years, or must I use black stove pipe. What is the difference? Answer: Depending on the height and draw of the chimney, it would probably work either way. However, a full liner definitely makes it easier to clean and will draft better. I see no reason why you could not use galvanized smokepipe if you only intended the installation to be temporary. This would not meet the codes for relining a defective chimney, but since you are relining a sound chimney it should be OK. It will probably last from 3-6 years, depending on weather and other conditions. A Stainless Steel liner will withstand corrosion much better and should last 10-20 years or longer.