How Buildings Learn: What Happens After They're Built

by Stewart Brand

It strikes me that external walls can take either a High Road or Low Road approach, encouraging either permanence or change. In some buildings you might want the front to be impressively High Road and the back adaptively Low Road. Low Road walls offer a further choice—they can be funky or high tech. One of the best of the funky is the highly forgiving board-and-batten. It doesn’t need precise fitting and can ignore wood expansion and contraction from moisture and temperature. Anybody with a hammer and saw can make or unmake a decent board-and-batten wall. For high-tech Low Road walls, the current acme is the variations on Dryvit known in the trade as “exterior insulation and finish systems” (EIFS). Light and cheap, they are factory-made panels of stucco and foam insulation bonded together, shortcutting weeks of work in wall construction. They can be molded to decorative shapes and look right nice in a movie-set sort of way, at least for a while. If they show dents after a few years, or the bonding compounds loosen, it is no great loss to replace them, maybe with something more lasting.