I use double wall pipe downstairs and triple wall through the attic out the roof. I burn pretty hot most of the time and my smoke output is generally low. Question is: do I need to be sweeping every season? Some people say yes, and others never sweep. A guy whose family had an Earth Stove in the 70's / 80's said they never swept for the whole time he remembered and never had any chimney fire. Is chimney fire more common with masonry chimneys or is it likely in stove pipe with an EPA stove running hot generally? I don't want to be penny wise pound foolish, but I also don't want to be crawling around on the roof in December.