Corridor Pressurization System Performance in Multi-Unit Residential Buildings

Corridor pressurization based ventilation systems are pervasively used to ventilate mid- to high-rise multi-unit residential buildings in North
America. This paper summarizes a study evaluating the performance of these systems based on an experimental program conducted at a case study building which has undergone an energy efficient building enclosure retrofit. In particular, the efficiency and effectiveness of these systems at providing ventilation air to the zones of the building will be assessed, along with the interaction between the ventilation system and the exterior environment.

The experimental program carried out at the case study building includes measurement of airflow rates provided by the make-up air unit,
measurement of flow rates between zones of the building using perfluorocarbon tracer methods, and long-term monitoring of pressure differences. Exterior conditions including wind speed and direction, temperature, and relative humidity were monitored using a weather station installed on the roof of the building to allow for evaluation of the interaction between the building and the exterior environment. Pressure equalized airtightness testing was also performed on a sample of suites to measure the airtightness provided by both the exterior enclosure and interior compartmentalizing elements. The results of this extensive experimental program are presented and conclusions are drawn with regards to the interaction of the driving forces of airflow (wind, stack effect, and mechanical ventilation systems) with the physical building to create airflow patterns in mid- to high-rise multi-unit residential buildings. The performance of the corridor pressurization ventilation system is specifically evaluated including discussion of its limited potential for use moving forward due to generally poor measured performance and increasing energy efficiency and indoor air quality expectations.

Overall, this study works to improve the understanding of corridor pressurization based ventilation system performance as well as the general
understanding of airflow patterns in mid- to high-rise multi-unit residential buildings. This knowledge can then be applied to the design of improved ventilation systems and compartmentalization strategies for these buildings. Effort is made to extend the conclusions of the study to meaningful recommendations for industry.

This paper was presented at the 2014 ASHRAE Annual Conference.