Hydronic raduiant heat in new tf home

I am in the process of designing a new timberframe home to be built in the the St Louis area next year. Does anyone have any experience in using the exterior wood-burning furnaces to run a hydronic radaint under floor heating system in tf homes? How do you do the second or third floors? Aer they efficient? What about cooling?
Thanks for the input in advance.
dave stine

Check out the Radiant Panel Association for info. http://www.radiantpanelassociation.org/ Out door furnaces have very poor efficiency but that's the payoff for not having the mess in your home. If your planning on burning wood and want efficiency, check out masonary heaters. http://www.mha-net.org/
Good Luck
Mark