This sort of is a result of the Power Venting question I had. It has been determined that I can most likely use an existing Chimney Foundation and just complete it. So talking with my father (the Bricklayer) he asked me if it should be 8 x 8 or 6 x 12.
I told him I would find out this answer.
The Stoker will be an EFM SF520. It will sit next to my current oil boiler and there will be two chimneys basically right next to each other.
the chimneys are 2 stories high so most likely 25' or so or maybe more even 30' possibly.
Thanks for your input.
One other question is there any particular things we should do or look for while constructing the chimney? I assume maybe put a cleanout toward the bottom of it? There is no cleanout on the other chimney.