Massachusetts’s 4D Home was one the most affordable in the competition. “We wanted to maintain affordability while still going after that high-end performance,” says Spencer Culhane, the team’s project manager. “But most importantly, we wanted to create something that a family would actually move in to.”
Unlike many of the studio-style designs in the competition, the 4D Home incorporates a divided layout, much like a traditional New England home, and features a gabled roof and exposed beams. The team attached a 6.5-kilowatt PV array to an offset trellis. “Architecturally, we were wondering what else a PV array could do beside generate electricity,” Culhane says. “We came up with this concept of a covered entry sequence on the south façade. It passively shades the windows, but from a service standpoint, those panels are much more accessible than if they were just mounted on the roof.”
The trellis also supports the home’s solar hot-water system, which incorporates six flat-plate collectors on the west side of the PV array that bolt to the back of the panels. The collectors help cool the array while generating up to 70 percent of the domestic hot-water load, according to Culhane.
The team’s main focus: reducing the size of the mechanical system by limiting the house’s baseline energy consumption. “We went with blown-in fiberglass insulation and closed-cell polyurethane spray foam,” Culhane says. “The focus of our project wasn’t to showcase the next innovative eco-friendly material, though we have a sensibility toward it. We thought the real goal was energy efficiency over the long term, so we went for a lot of off-the-shelf products. The end result was something pleasant and livable, but that didn’t have that marketable spin where all the products are reclaimed or cradle-to-cradle certified. We were okay with that in the end.”
The 4D Home was sold to a Maine couple, who have agreed to share their energy-consumption data with engineers. “It can all be monitored online,” Culhane says, “but it’s a private residence.”
Estimated cost: $267,913.06