Hi all, newbie here. So I bought an Englander cub to heat my shed. I won’t use it much, a few times a year when I stay overnight and the temp drops below 40. Anyway, it didn’t come with a flue collar. Do I need one? I see the sell them, how do I install it? I am going to put this in the corner and vent it through the roof. I’m probably going to get a double wall pipe, but will still put some sort of heat shield on the walls. Thanks!