you may take advantage of the book The Cabin Stove, by Max Edleson i think its over at
http://firespeaking.com/
and even look up batchbox to fit in front of your fire place and build according how you get permission from men that can tell you what you can do with your own property.
another guy is talking about a fireplace conversion here also.
Building rocket stove out of soapstone slabs
building to code, worrying about code and asking permission? all those things are part of this topic and have not been a part of this country in its conception for a good reason. its a shame we have to "worry about" permission. i do not have code enforcers in my area and its a shame you do. its all part of the UN agenda 21 international law program and we have for lack of being involved allowed these punks to change our foundation. freedom comes with responsibility and you can not legislate responsibility no matter how many codes you put in place. i could not live in your area with a bunch ninnying authoritarian b@stards up my back side for no good reason than to boss you around.
another idea is to make your system mobile like did and put it on wheels to pull it away when your inspector... er um i mean when spring comes and you dont need heat anymore.