It’s a fact of physics that hot air rises, and this simple concept is all Maria and Matthew Salenger needed to design a passive cooling system for the backyard pods they use as bedrooms at their house in Tempe, where the average daily temperature is 86 degrees. The light, steel-framed structures float on stilts above the yard, allowing cooler air to circulate underneath. On hotter days when this isn’t enough, operable windows along the roof line and vents in the floors allow hot air to escape out the top and draw the same cooler air up from the lawn. By relying on this energy-efficient system during all but the hottest months (when 

they run a small air-conditioning unit only in the evenings when they’re home), the 

couple, who work together as the architecture firm coLAB, has chopped their monthly power bills in half—no small feat in a climate where summertime temperatures can top 115 degrees.  The Sky is the Limit by Ivane Soyombo