A Parametric Analysis of Internal Airflow Patterns in Supertall Passive House Multi-unit Residential Buildings

In the face of accelerating climate change, a growing need for high density housing, and the demand for excellent indoor air quality through suitable ventilation, this study simulates internal airflow patterns of a supertall, multi-unit residential building (MURB) using parametric analysis on 87 steady-state models in CONTAM. Research is expanded from prior investigations of cold climate MURBs to the CTBUH 300 m supertall height criteria, and Passive House level airtightness. Corridor pressurization and direct-to-suite ventilation systems are modeled to predict the suitability of each system for this typology. Stepped outdoor temperature ranges identify the cold climate impacts The findings suggest vertically compartmentalization of core shafts most effectively reduce stack pressures leading to internal airflow spread. Secondly, improved airtightness of internal pressure boundaries should be applied from the core outward, in conjunction with a slightly pressurized corridor and balanced in-suite ventilation. Improved airtightness of suite doors is highlighted as a concern where other mitigation measures have not been applied, as stack pressures can become too great for ease of door operability. This study emphasizes that a Passive House envelope alone will not eliminate stack-induced suite-originating contaminated airflow.