Natural ventilation has been identified as one of the sustainable strategies for achieving indoor thermal comfort, but the effects of  wall openings on natural ventilation in educational buildings are yet to be properly investigated, especially in the hot-humid tropical environments. The aim of this research was to investigate the effect of size and position of wall openings on effective natural ventilation for good thermal comfort in the classrooms of public primary school buildings in Enugu metropolis, Nigeria. An experimental research design involving the use of two data logging instruments (thermo-anemometers - AZ 9871) was adopted in measuring wind velocity, relative humidity, and temperature within and outside the classrooms of 60 public primary school buildings in the study area. Global ventilation coefficient and wall porosity standards and linear regression analysis were used to analyse the data. The results show that the average wall facade porosity of the buildings was relatively high at 51%, which is more the standard architectural wall porosity benchmark of between 30%-40% and that the mean natural ventilation efficiency of 80% above the 60% global ventilation efficiency standard was achieved. In addition, the sizes and positions of wall openings had positive significant effect on natural ventilation efficiency, which in turn influenced the thermal comfort conditions of classrooms investigated. Findings of this study are instructive in noting that in order to achieve thermal comfort in classrooms via natural ventilation, architects and other building design professionals should endeavour to give adequate attention to the size and positions of wall openings in classroom buildings in the hot-humid tropical environments.

classroom buildings, natural ventilation, primary schools, thermal comfort, tropical environment, wall openings.

Received: January 7, 2021; Accepted: February 23, 2021; Published: April 12, 2021

How to cite this article: Emeka J. Mba, Francis O. Okeke and Ugochi Okoye, Effects of wall openings on effective natural ventilation for thermal comfort in classrooms of primary schools in Enugu metropolis, Nigeria, JP Journal of Heat and Mass Transfer 22(2) (2021), 269-304. DOI: 10.17654/HM022020269

This Open Access Article is Licensed under Creative Commons Attribution 4.0 International License

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