Newbie and first post: Questions on stove size, flue install

Greetings Hearth Room members,

We live just outside Boston and are close to making a decision on a wood stove purchase and install.

We live in a 4500 SF 2 story home. You could call it a 2 story contemporary ranch. It is built on a slab. Insulation is fair to poor in my opinion.

The challenge today is heating the great room, which is 30' long by 27' wide, with an 18' ceiling. Off the great room are two wings, with various living and sleeping areas. You could say the first floor is largely open plan. Really it's the great room, a library off to one side, and a tv room off to the other side, that need the heat. If heat manages to meander to further areas, that's bonus.

Questions

I am looking at very large stoves, cast iron, enameled, in the 80k btu range. Is this the right size? We have trouble heating this room in cold weather, and I'm looking to make it nice and warm.

The house has a flat rubber roof. The plan is to do double wall pipe inside the great room, all the way up, and penetrate the roof. What's your opinion on that? We could also go up to the ceiling, 90 out the side wall, then 90 again and go up, and avoid touching the rubber roof altogether.

I could send a pic of the room if that will help.

Thank you!

And by the way I read all the stickies.

Thanks FFJ - The Chief of Household Operations likes the look of cast iron, a large viewing window, and is partial to enamel finishes. I may lean toward non catalytic to keep running the stove a little less fussy. Other than that, I just want a brand that is reputable. From what I have learned, it's all about the install.