Out of curiosity why ducts and not floor pipes for heating? Especially in a climate where you can live without AC if: 1) you make your walls thicker and as you mentioned well insulated---which helps in the winter too! 2) you have "real" blinds on the outside of your windows.
Not sure what you mean, but just open street view on a random housing unit in Italy or Spain, and compare that with a random housing unit in Belgium or Denmark.
Blinds on the outside keep heat away from the glass and avoid turning your house into a greenhouse.
You meantioned ""real" blinds on the outside". I've lived with these in Germany years ago (modern construction, totally integrated into the window design). I recently started thinking about this in the context of an east facing window wall in NM, which could use some solar blocking for 3 months of the year. Wondered if you were thinking of any particular kind of ""real" blinds on the outside" ...
Places that have big storms have these things called storm shutters, but I haven't seen a home that has it for thermal reasons. My experience is limited to the Midwest United States though.
I'm pretty sure that either German-style roller shutters or louver shutters would accomplish the goal. As long as the sun gets prevented from hitting the window.
There won't be a climate where you can live without AC in the next 20 years.
Anything south of upstate NY is already pretty unbearable in the summer. Another added benefit of AC is the dehumidification of your interior, which means less mold.
