A comparative study of the resource requirements for external plaster finish of concrete block wall versus earth brick wall

Abstract

This dissertation entails a field measurement study that involved collecting and utilizing primary data for analysis criteria. Generally, in building construction there is less knowledge on the volume of plaster and time expended to plaster either earth bricks or concrete blocks thus leading to adverse delays in project decision-making. The study’s main objective was to establish differences in resource requirements for external plaster finish of concrete block walls versus earth brick walling units. A total of thirty (30) commercial construction sites were sampled. The selected walls were subjected to quality-qualitative assessments (expert view options) that involved interview questionnaires, quality-quantitative measurements, and resource requirements determinations. This involved the aid of instruments (theodolite & Vernier caliper) and measurement tools such as the data collection sheets for primary data collection. The data analysis first involved the generation of series plots, regression analysis, and T-test statistical comparison that guided to ascertain of other differences in the data collected. The major findings showed walls of concrete blocks consumed fewer material requirements (m3 /m2 ) across all the wall qualities (good [0.026], fair [0.028], and poor/bad [0.030]) compared to its counterpart the earth bricks (good [0.030], fair [0.037], and poor/bad [0.048]). The percentage difference comparisons of the same wall quality resulted in 12.3% in good, 28.7% fair, and 45.8% poor. The categorized work crew was also considered. Also, the man-hour requirements expended in earth bricks during plastering executions showed that more time was recorded in earth bricks than in concrete blocks. On average, the hrs./m2 in good [0.134], fair [0.137], and poor [0.142] wall qualities in concrete were computed with those of the earth bricks good [0.193], fair [0.209] and poor [0.265] that resulted to percentage differences of 36.1%, 41.6% and 60.6% across the respective wall qualities comparisons. Concrete block assessments in this study showed better wall quality aspects compared to the earth bricks i.e., the walls built with concrete blocks showed less raggedness and better wall inclinations in relation to the earth bricks. The study showed significant differences in resource requirements for external plaster finish activities in concrete blocks versus earth bricks. Therefore, the study recommended construction industries should use bricks rated as good quality for masonry wall erection where it’s the only construction option, fewer resource requirements will be expended on external plaster finish otherwise concrete block walls had better benefits than earth brick walls.