Effects of Natural Ventilation On Users’ Comfort in Administrative Buildings in Southwestern Nigerian Federal Polytechnics

Abstract

This study assessed the effects of natural ventilation on users’ comfort in selected administrative buildings of Federal Polytechnics in Southwestern Nigeria. A mixed-method research design was adopted across Federal Polytechnic Ede, Federal Polytechnic Ado-Ekiti and Federal Polytechnic Ilaro. Data were obtained through structured questionnaires, physical observation, field measurements and interviews. A total of 295 valid questionnaire responses were analysed alongside qualitative observations. Findings showed that the surveyed buildings were predominantly low- to medium-rise, with cellular office layouts, operable windows and mixed-mode ventilation systems. Natural ventilation was strongly recognised as beneficial, with the statement that natural ventilation improves indoor comfort recording the highest mean score of 3.71, while comfort without mechanical cooling recorded the lowest score of 2.99. Cross ventilation was mostly rated fair, with 40.0% of respondents reporting fair performance, 20.0% poor and 10.2% unavailable. Interview findings further identified thermal discomfort during hot periods, dependence on mechanical cooling and uneven airflow distribution as major concerns. A very strong positive association was observed between ventilation quality and users’ comfort and work performance (r = 0.98), although the relationship was derived from four paired mean observations and should therefore be interpreted cautiously. The study concludes that natural ventilation contributes meaningfully to comfort and workplace performance, but current building configurations do not consistently provide satisfactory conditions. It recommends improved orientation, operable window design, cross-ventilation, shading, airflow pathways and reduced dependence on mechanical cooling in future administrative buildings.