Prefab+Net Zero+Passive House in the Colorado Rockies, Yes Please!
Last Updated: Apr 13, 2025In 2014, Bill McDonald took a bold step and built Michigan's first prefabricated, panelized Passive House. He was ready for the challenge.
Since he was a kid, McDonald had suffered from severe allergies—from dust, dirt, mold, and mildew, inside and outside the house. So, after college, he began learning about LEED, sustainable building, retrofitting homes for cleaner air, and the Passive House Institute US (PHIUS). For several years, McDonald ran a business retrofitting homes to be more sustainable and healthy for occupants. Then, he attended a PHIUS conference and earned his certification as a Passive House consultant, which brought everything home.
He put together a team that retrofitted a two-story, 1,600-square-foot home in Detroit. The deep-energy retrofit included extra insulation, superior windows, air-tight detailing, and fresh air ventilation. The blower door test showed 1.0 ACH 50. More homes followed. Still, McDonald wasn't convinced that retrofits on existing homes were an ideal solution for every homeowner. In other words, instead of fixing problems, he wanted to create the right solution from the get-go through smart planning and design.
McDonald began investigating the possibilities for a new, prefab, panelized Passive House. As his mother was looking for a new home, he decided to start with her. He consulted with Passive House experts in Portland and Vancouver, BC, to Americanize the German-based building methodology. Then, he began developing what would become the prototype for his company, Phoenix Haus.
With pre-cut lumber from the Pacific Northwest, a Swiss carpenter creating the drawings, and McDonald running energy modeling software, the team assembled and finished the 2,300-square-foot home, the first PHIUS-certified home on a two-acre property in rural Michigan. His Mom hardly felt that winter's below-freezing temperatures, as the house stayed at about 68 degrees. Moreover, her energy costs fell below $75 per month.
Table of Contents
- Getting to Net Zero
- A Prefab Healthy Home
McDonald had learned that a Passive House could be designed and constructed off-site, in a controlled setting, and assembled on location—and deliver superior comfort and energy performance. "Phoenix Haus Brings Prefab Passive House from the Midwest to the Colorado Rockies. Since then, we've stuck to our commitment to prefabricating while building at Passive House standards," he says, "whether or not the homeowner seeks certification."
After building throughout the Midwest, McDonald set his sights on the West—namely Colorado, where the economy was booming, and the population is full of health-, energy- and environmentally conscious homeowners. After receiving certification for its Alpha System with the Passive House Institute (PHI) in Darmstadt, Germany, (lightweight wood frames, insulated with cellulose and exterior wood-fiberboard), the company was ready to make its mark. It's doing so with the recently completed 1,900-square-foot "The Homestead 19" (H19), a pre-programmed, off-the-shelf design.
Getting to Net Zero
Phoenix Haus has worked through numerous iterations of its prefab Passive House designs, landing currently at H19. With each iteration, H is for Homestead. H19 is net-zero due to its Passive House design, Alpha system super-insulated roof and walls panels, triple-pane exterior doors and windows, 12 solar panels producing a 4kw output, and heat pump. The walls are R50, and the roof is insulated to R70.
Camille LeFevre
Camille LeFevre is an architecture and design writer based in the Twin Cities.
