Plum Projects is a Phius Certified Passive Home Builder in Seattle.

Whether you’re planning a high-performance new build, a net-zero home, or simply want to make your existing home more energy-efficient, Plum Projects has the training and experience to get it done right.

As Phius Certified Builders, we are trained to meet the rigorous standards of the Phius passive building program, North America’s leading passive house certification, developed in partnership with the U.S. Department of Energy.

Building to the Phius standard means constructing homes that use dramatically less energy while delivering superior comfort, air quality, and long-term durability. This is achieved through a combination of continuous insulation, airtight building envelopes, thermal bridge-free construction, and high-performance mechanical ventilation. The result is a home that stays consistently comfortable year-round, with heating and cooling costs reduced by as much as 70–90% compared to a conventionally built home.

Beyond certified passive house projects, we bring this same high-performance mindset to every project we take on, applying passive building principles wherever possible to improve energy efficiency, indoor air quality, and building durability, regardless of whether full certification is the goal.

If you’re curious about what passive building could mean for your project, we’re happy to talk through the options.