Back in the late seventies when Cliff Butler was ready to build his dream home, he was looking for one thing: a southern-facing slope.
This then-33-year-old pharmacist from Chapel Hill, North Carolina claims his friends thought he was crazy. He had never heard of global warming, but he liked to save money and he believed in conserving resources.
For the past 30 years the Butlers have lived in a home they watch being heating and cooled by the sun.
“Until you live in a glass house I don’t think you notice as much how the sun moves,” explains Cliff Butler. “We see it move daily.”
The Butlers rely on the power of the sun, and passive solar design, to help heat their home in the winter and cool it in the summer.
The southern-facing side of their home is nearly all windows to take advantage of seasonal variations in sun. The north side is mostly buried in the side of a hill to take advantage of the constant temperature of the ground.
In this video, Cliff gives us a tour of their “glass house”; he shows us the stone floor that acts as a heat sink, their fans for moving warm or cold air, their deep eaves and deciduous trees that block summer sun, natural daylighting and all those windows.