Detailing a chimney
I know, I know—if I really wanted to be efficient, I would eliminate the chimney. However, I love a good fire and the warmth from it. So, my new house will have a zero-clearance wood-burning unit (RSF 320).
The chase for the chimney is mostly inside the envelope, except for a portion at the top. I have attached the rendering to show what it looks like from outside.
I am wondering how exactly to air seal and insulate this in an ideal manner. I have attached another simple diagram trying to delineate the air seal. This house will have a spray-foamed, unvented attic space. Is it feasible to seal this chase up? Should I insulate only that upper area that is partially outside the envelope or insulate the whole chase?
That is a great room to the left, with a 17′ tall ceiling — so I don’t think i need any fire stopping midway up the chase, but could add it if it would help seal it up. The plans are rather vague on the details here so I would like to be ready when the hammers start flying (or nail guns, as the case may be).