Hi Daniel; Welcome to permies! I'm sure that you will hear from a
local rocket builder soon. I moved away from new england 35 years ago, at that time I was in vermont where everybody had a
wood stove and there were no regulations (other than
common sense ) on what you could have. I assume that NH would have been the same (at least in the rural areas) . In these modern times there seems to be a "rule" about everything ! If your home already has a
wood burner then only a guest would see your super cool
RMH, no need to tell anybody in authority that you are smarter than they are! If you are rural and your neighbors burn wood then build it... after startup the only thing coming out your chimney will be steam! Nobody will know its not a large
dryer vent ! (lol) In truth a properly built
rmh is so much safer and so efficient that states
should REQUIRE that you build one if you burn wood ! (Fat chance of that !!!) Learn the local regulations about masonry
heaters ,or lack of ... get some fire brick and clay ,build practise rmh's in the backyard before trying to build in your home. Hopefully a local (Live free or die) RMH builder will respond to you soon. Don't give up, even in the case of senseless rules made up by ignorant bureaucrats who are more interested in keeping their job than improving the world we live in .