The project had to satisfy two demanding standards at once. Passive House certification requires strict airtightness and energy recovery. Modular construction requires every connection to land within tight tolerances, with no room for adjustment in the field. Once the modules left the factory, changes were not possible, so riser connections and plumbing tie-ins had to be set precisely before fabrication. Indoor air quality carried extra weight here, since the residents are seniors. The ventilation had to supply continuous fresh air while holding heat inside the building, and the HVAC had to run on the ultra-low energy loads Passive House allows. Plumbing fixtures had to meet Enterprise Green Communities water efficiency criteria. A COVID-related pause stopped the project from 2020 to 2022. When fabrication resumed in 2023, the engineering package had to still be current and buildable, ready for the modules to arrive on site that October.