Hi all ,I'm in the middle of making a log burner for my shed out of a gas bottle ,I've got the flue it's 41/2 inches in diameter and 2 meters long.now my question is has any body used the flashing kit they got on ebay for metal roofs as mine will be going through a meal coragated roof or is there any other way of doing it with out it leaving the rain in it will be single skin so it needs to be heat proof .ps do you buy the cowl or make one thanks gareth