Synopsis: When Asheville, N.C., builder Brian Knight built his first passive-solar house, he could tell that something was different: Even unfinished, the house was bright, comfortable in cold weather, and drier than the typical home. The experience made him want to get more involved with passive-solar design, but he needed two things: a few building lots with southern exposures, and a simple, 3BR, 2B plan that he could easily adapt to different sites and clients. The first he could buy; the second he had to devise. The result was his “Springtime Cottage,” a traditional-looking house specifically designed to take advantage of the sun. By altering the plan only slightly, he has built three Springtime Cottages on various sites in Asheville, each time tweaking the design slightly to adapt to the site and his client’s wishes. In this article, Knight lays out the passive-solar features he focused on in designing the cottage (envelope air-sealing and insulation, window selection, thermal mass, and overhangs) and explains the adaptations he made over the course of three builds. Photo courtesy of the author.

Building in harmony with nature has always made sense to me, but the consequences of not doing so hit home when I through-hiked the Appalachian Trail after high school. Along the way, I saw trees withering on ridgetops and tasted snow tinged with coal-stack pollution. In the middle of the woods, I could still hear the drone of combustion-generating traffic. The experience would never leave me.

As a biology major at Appalachian State University, I gravitated toward sustainable building and graduated with degrees in construction and appropriate technologies. After working for a time with a large national home builder, I set out on my own. I wanted to return to what I had learned in college about how a well-constructed…