Hi all,

First time poster to this forum so please be kind!   So I thinking through the plans for a new house build. It will most likley be slab on grade, SIP wall and roof, and at least 1-1/2 to 2 stories.  The climate is a pretty even mix between the need for heat and cooling.  I am strongly considering radiant heat tubing in the slab, maybe in upper floor also. For A/C likely mini-split units to again allow zones. 

So here is question; I have also been thinking about a small section 8x8, 8x10,  that extends to a full 2-1/2 - 3 stories.  In this section would be windows (that really open!) that would allow cross flow vent of hot air with and structure. So this area would be near the middle of the house and have large opening (like stairwell) to promote air movement. So what if, I mounted a collector grid (just pipe and fins, no containing box or glazing) near the ceiling line of this section. Could I trap and collect heat that raises from below (like radiant or from a wood stove/fireplace) and recycle this into the solar heat storage or the floor?  I think of it as a way to move heat from area not used to one that is.  Thats during heating season.  During cooling season, could these be used again to collect heat and divert it elsewhere, like to storage or to dump. 

Has anyone considered this? Tried this? Your thoughts? 

AjcCmc  

To get a good heat exchange you need turbulence/motion, which you won't get at the ceiling. Better to mount the HX on the wall, (in direct sun, where possible), to induce convective air currents. The difference in heat exchange rates at the same temperature deltas will be several-fold higher that way.

This sounds like a cross between a passive solar-atrium and solar chimney. To prevent severe summer overheating you'll need some conbintation of shading and ventilation. With both top & bottom operable vents at 2.5 story structure will have enough stack effect to reasonably self-ventilate. A decent solar designer should be able to ballpark the performance for you.