Boston architects Eric Höweler and Meejin Yoon are internationally renowned for their pioneering architectural and urban design projects, but in their recent concept for Meejin’s parents, Hannah and Jason Yoon, the vanguard couple took a more restrained tack. “It’s a simple house, with a few flourishes,” says Höweler, “less exotic, more practical, a little funky.” One embellishment is a small courtyard, born of restrictions imposed by budget, a narrow site, and strict zoning laws.

To maximize square footage and adhere to setback regulations, Höweler and Yoon planted the house dead center in the parcel, leaving little room for outdoor space. Riffing on a courtyard—“one of our ongoing interests, or obsessions,” says Höweler—the duo designed an inlet that satisfies Hannah and Jason’s desire for a meditative bit of greenery with a water feature.

“In every project, we try to do one thing that’s handmade, a custom design where the only way we could afford to do it is if we did it ourselves,” says Meejin. They rolled up their sleeves and, with the help of Meejin’s brother and David Costanza, a former student and employee, spent two weeks building the formwork to mold the concrete for the fountain. They found a local supplier who custom-colored the cast concrete a shade darker than the house’s CertainTeed–clad facade. Stainless steel channels guide water through the three-tiered design; benches topped with ipe provide a place to sit. Dwarf Japanese maples, wild grasses, and white beach pebbles from Sumatra break up the otherwise gray palette. “It’s small but we wanted it to feel like a very designed outdoor landscape,” says Meejin of the thoughtfully selected and affordable details that make the whole garden feel far greater than the sum of its parts.