Sensitivity analysis of proposed natural ventilation IEQ designs for archetypal open-plan office layouts in a temperate climate

ABSTRACT Designing naturally ventilated deep, open-plan offices could improve occupants’ thermal comfort and productivity and ensure energy reductions; however, this can be challenging when relying on façade only openings. This research examines the ventilation performance sensitivity of atria, innovative façade openings and interior layouts of open-plan offices, in order to identify optimal typologies. Different building typologies are developed through a combination of various atria designs and configurations, with the effective use of high-aspect-ratio (HAR) openings with a similar dimension to that of the floor-to-ceiling height, in either a mid-level vertical (MLV) or high-level horizontal (HLH) orientation. Steady-state computational fluid dynamics (CFD) simulations are performed to predict internal airflow and temperature distribution in a moderate climate and water-bath modelling (WBM) experiments to validate the computational models. Results showed that MLV provide superior cooling potential (up to 2.5°C reductions) and higher ventilations rates; despite, increasing thermal gradients. Unobstructed atria with a horizontal profile similar to that of the building footprint also performed well. Overall, façade opening design was shown to be the most influential design parameter. This research has presented guidance based on reliable results to better equip building designers and architects in the design of successful naturally ventilated deep, open-plan offices.