permaculture

[zack@riseup.net]

Hi -

I've got a newfangled high-efficiency wood burning  fireplace insert,  
which heats our main living area nicely, but the back bedrooms and  
other extremities of the house remain pretty frigid most of the winter.

I'd like to rig up some kind of ducting system to distribute heat more  
uniformly, but I'm not quite sure where to start. I'm familiar with  
thermo-siphon systems used to assist hot water heaters in winter. My  
challenge is that it's a single level home, so I don't have the  
benefit of much elevation gain to assist a convection cycle. If I  
ducted the heat off of the back of the flue, would I be able to place  
vents on the floor of the back rooms? Would the vents need to be  
higher than the heat source? Say if I put them midway up the wall,  
higher than the heat source, would they vent heat properly even if the  
ducts have to dive under the floor after getting their heat at the flue?

Does anyone have any experience with this? I guess I could use a  
blower, if necessary, but I'd like it to be passive.

Thanks for your suggestions,

Zack