Hi Cherie; Welcome to Permies!
Most of the installations that I have seen, on a single pitch roof.
Just use a standard roof jack and metalbestos insulated pipe going thru the jack and outdoors.
I have seen photo's of the style you are referring to and if it were me , I would put insulation up very close to the box.
Have you considered a
rocket mass heater as your
wood burner?
We have a forum all about them here at Permies!