I have a 3100 sqft fiberglass flat roof with a shingled 10x24 nearly dead center on an angle. I cant find much information on the extended length of the exhaust for this situation. The previous homeowner has a wood burner installed. But when they moved(forclosed) they took it and the entire flute less the part that was embedded in with the shingles. My concern is that the exhaust is near the edge of the shingled part, not over the ridge(I dont have a ridge as in most homes, mine goes straight down about a foot then windows), but the heat, residue getting on my fiberglass roof section. Also being in Az I dont want to start a wildfire. Any suggestions will be much appreciated.