The building has officially achieved Passive House Certification, making it a standout example of high-performance, low-carbon residential development in Ontario. What makes this project especially notable is its use of a fully prefabricated concrete structure and enclosure system—a unique approach within the Passive House realm. The total precast construction method supported energy performance goals while streamlining construction and addressing air barrier continuity and enclosure durability.
With precast components manufactured off-site, the building has come together with exceptional speed, resulting in significant cost savings and quicker occupancy. The building followed an accelerated schedule, having been erected and weathertight within 12 weeks from the arrival of the first precast panels to site.
RDH served as the Passive House and Building Enclosure Lead, supporting the project from early design through construction and final certification. RDH provided detailed guidance on enclosure design, thermal performance, moisture control, and airtightness. The scope also extended to factory visits to Stubbe’s precast manufacturing facility to review the prefabricated façade elements and observe in-plant quality control procedures. These visits included oversight of mock-up testing for air and water performance, focused on panel joints and window installations.
The team also conducted whole-building airtightness testing and worked closely with the design-build team to align with Passive House standards.
RDH’s leadership in Passive House consulting and building science integration ensured that performance goals were met while supporting the project team in adopting prefabricated methods.
With Passive House certification now achieved, Imperium sets a new benchmark for mid-rise residential buildings in Ontario. It demonstrates that high-performance standards can be successfully met through prefabricated concrete construction, making it a strong candidate for broader industry learning and future case study publication.
