Effect of Geometry of Shading Devices on Quantity of Indoor Heat Gain in Residential Buildings in Southeast Nigeria. A Case Study of Owerri

Abstract

The challenge of excessive heat gain in buildings has become a major source of concern, especially in residential buildings. This is because the build-up of heat within indoor spaces of residential buildings causes thermal discomfort for the occupants. The objective of the study was to examine different geometries of shading devices and their effect on the quantity of indoor heat gain in residential buildings with a view to developing design strategies to reduce heat gain in residential buildings. The research was designed as a field survey. Out of the 13 residential layouts within Owerri, five (5) homogenous layouts were chosen as a representative fraction because of similarity in environment and proximity to each other. Out of a total population size of 1570 shaded housing units, a 5% rule of thumb was applied to select a sample of 79 for the survey. Data was collected using observation schedule and data loggers. The variables in focus were interval variables; hence, Pearson’s Product Moment Correlation Analysis tool was used to examine the significance of the relationship at 95% compliance. It was found that there was no significant relationship between the length of projection of the horizontal overhang (with integrated vertical fins) and average heat gain in residential buildings in Owerri, Nigeria. It is therefore recommended that the use of shading devices should be encouraged; education and awareness of appropriate principles for effective implementation of this shading instrument should be robustly conducted in the study area.