Trombe walls use glass and masonry to collect and evenly distribute solar warmth, Mella explains, and today's dual glass walls also trap heat in winter and counter heat gain by means of air movement in summer.
While the concept has backers, some professionals (and most U.S. curtain wall manufacturers) remain unconvinced. A few outspoken critics even hail from Germany, where strict energy codes and workplace regulations for minimum daylight levels and views make it a Mecca of dual-skin structures. Such rules and incentives are more rare in North America. So, while European dual-skins number into the thousands, only a handful exists here.