Using Compartmentalization To Mitigate The Impacts Of Stack Effect In Tall Residential Buildings PDF Download

An investigation was conducted to the effect of decreasing the air leakage area across internal partitions of a typical modern high-rise apartment. The objective of this work was to study the practicality of increased compartmentalization or separation of the living units from each other and from the corridors and vertical shafts in the building. A 12-storey condominium building in Nepean, Ontario was selected as the test case for the measurements. Measurements of pressure difference across 18 different partitions in the building were made under cold weather conditions, with doors across some of the separations opened and make-up air fans either operating or switched off. A total of 20 measurement sets are presented. The airflow rates through the make-up air vents on each corridor were also measured. A computer simulation model of the airflow network within the building was developed using the CONTAM93 program. The simulation model was calibrated so that the simulated pressures and airflows matched those measured in the building. The doors were determined to represent the element of the interior partitions which could be improved most reliably and simply. It was felt that the best modern technology could produce interior doors providing 1/4 the leakage of the tightest doors commonly found in high-rise residential buildings. The effect of installing such tight doors in existing buildings was simulated. Three compartmentalization strategies were simulated, as follows: separating the units from the corridors, separating the corridors from the vertical shafts, and a combination of the first two. Separating the units from the corridors was found to have greater effects than separating the corridors from the shafts, but the combination of the two measures was nearly additive and created the greatest differences from the base case in air movement and pressure differences across building elements. Pressure differences across interior doors were increased by compartmentalization. Pressure differences across the exterior skin were reduced but not as much as expected. The combination strategy spread pressure differences across greater numbers of partitions, so that the peak pressure differences across interior doors were smaller with this strategy than the other two. Unit ventilation is more uniform under compartmentalization. Units on lower floors receive more total air and more of the air from the corridor, with essentially none from infiltration. Units on upper floors receive less total ventilation, and a greater proportion of their air is from the corridor ventilation system; virtually none is from the garage via elevator shafts and stairwells. Total air leakage, and airflow through the corridor ventilation system, is reduced by up to 14% by the combination strategy. Peak loads and required heating and cooling capacities are reduced by the same amount. The existing corridor ventilation fans were found to provide more than enough building pressurization, and corridor ventilation flow rates could be further reduced without much impact on the benefits of compartmentalization.