Local architectural practice Runberg Architecture Group has raised the bar for sustainable design in Seattle with the completion of Sitka, a LEED Platinum-certified multifamily development on target to achieve Seattle’s 2030 Challenge for Planning goals of reducing water and energy use. Built to use nearly a third less energy than the typical baseline design, the 384-unit development features numerous energy-saving systems — Sitka is the nation’s first multifamily project to use a Wastewater Heat Recovery system — as well as a stunning courtyard that mimics the Pacific Northwest landscape with a running stream, tree-covered hilltops and a lounge that resembles a treehouse.

large brown and tan apartment building in Seattle

Located in Seattle’s South Lake Union neighborhood, Sitka is a seven-story building centered on an outdoor courtyard. Runberg Architecture Group drew inspiration from Northwest Modernism and the landscapes of the nearby San Juan Islands to create the project. A sloping green roof and rooftop community garden help capture stormwater runoff as well. The tree-filled courtyard also features a fog system and a treehouse, designed by Seattle’s Lead Pencil Studio, that includes a working fireplace with views of the courtyard.

Related: Energy-efficient house embraces panoramic views of Puget Sound

lounge with wood ceilings and gray chairs
kitchen with light wood cabinets and dark wood floors

“Our mission is to design places where people want to be,” said Brian Runberg of the project’s human-centered design. “When creating Sitka, we asked ourselves what was missing from most of South Lake Union — what would make people feel good about spending time here — and it was green space. We wanted to create an oasis for residents and neighbors in the midst of the hard cityscape.”

semi-circle-shaped treehouse with a green roof in a courtyard
stone steps over a pond in a courtyard

To minimize energy usage, the architects strategically broke up the building mass to allow natural light and ventilation into the courtyard and interiors. The development also includes LED lighting, EnergyStar appliances, recycled and locally sourced materials, low-flow toilets and fixtures and a high-efficiency 14-foot-diameter fan in the fitness center, all of which contribute to the development’s energy goals.

+ Runberg Architecture Group

Images by Christophe Servieres and Michael Walmsley via Runberg Architecture Group