Can PHIUS scale to commercial?

Yes.

Passive house is orders of magnitude more efficient and easier to achieve than single-family residential. OK, maybe not orders of magnitude more efficient, but certainly much more.

Although plenty of single-family homes have been built to passive-house standards, the approach has been applied recently to multifamily apartment buildings and large-scale commercial buildings. The results are spectacular because meeting the energy codes gets easier as the surface-to-volume ratio goes down. Less insulation is needed in large buildings, and because more people occupy commercial and multifamily space than single-family residential, more heat is generated, which can drastically reduce the size of the heating system.

Even though there are a few things in your favor, there is still a learning hump for new designers and builders. Continuous insulation, airtightness, and balanced mechanical ventilation are less common in standard construction and may be challenging to scale up on the first project with a new team.

(image: courtesy of Rocky Mountain Institute)