On my old stove in Alaska, I installed double wall pipe which was vented at the top and bottom, this allowed a closer clearance but still recovered some of the heat from the stack. I am looking for similar to install in Arkansas, but I cannot now find that pipe, anyone know which brand of pipe comes double walled, vented? I think it was from a mfr in Texas, but I'm not sure....thanks for any replies and words of wisdom regarding such pipe. BTW, it was 8" pipe, now I'm looking for 6" pipe for a new, smaller stove.