No one in the modern era really believes that a castle built in, say, the 12th century is energy efficient, but a castle, with an outer wall and a keep within the wall, is what the South Lowell Apartments in Denver resembles from an aerial view. Perhaps that’s why the project team chose to use the phrase “square donut” instead.

Castle, donut or whatever term one chooses to describe the project, the fact is that this 100,200-square-foot multifamily residence designed as affordable housing is far more energy efficient than any castle. Additionally, much of the cost savings realized on the project—construction of which included renovating the original 73,581-square-foot building and adding 26,620 square feet of new construction—are due to the apartment building’s design.