The purpose of the research described in this paper is to evaluate the range of applicability of the method developed in ASHRAE Research Project 763 (RP-763) to estimate tall building infiltration at main entryway doors. This method is published in ASHRAE Handbook of Fundamentals 2009 and therefore quite widely used. An estimate calculated using this approach is compared to values for a number of scenarios using a multi-node airflow analysis tool. The example shown in ASHRAE Handbook of Fundamentals 2009 is reproduced using a model with differing air path areas representing small, medium and large footprint buildings, three different construction tightness levels, and two different wind pressure coefficients at the main entryway. All simulations produced infiltration estimates ranging from 8.5% to 44% of the estimate shown in ASHRAE Handbook of Fundamentals 2009. It is important for designers to know what the limitations of the estimation method are so they can make informed choices about when to use more advanced analyses based on actual air pathways and construction tightness levels. The comparison of the estimation method and a more detailed analysis provided in the present paper provides information to support designers in this decision.

Keywords: Infiltration, automatic doors, tall buildings, envelope, modelling, IES Virtual Environment