Evaluation of Sustainable Building Materials and Their Cost Implications for Residential Construction in South East Nigeria

The use of sustainable building materials offers potential for reducing the environmental footprint of residential construction in Nigeria while addressing cost challenges associated with imported conventional materials. This study evaluates the performance characteristics and cost implications of selected sustainable building materials for residential construction in the South East geopolitical zone. A mixed-method design was adopted, combining laboratory performance testing of three locally available materials (compressed stabilised earth blocks, bamboo reinforcement, and recycled aggregate concrete) with a cost analysis based on 40 residential project cases in Anambra, Enugu, and Imo States. Cost-benefit analysis and descriptive statistics were employed. Findings reveal that compressed stabilised earth block walling offers cost savings of 28% compared to sandcrete block construction in the South East region, while maintaining adequate compressive strength for low-rise residential applications. Bamboo reinforcement demonstrates structural viability for non-load-bearing members at 40% cost savings over mild steel, though fire resistance and treatment costs reduce net savings. Quantity surveyors are largely unaware of the cost benchmarks for these materials, inhibiting their inclusion in project estimates. The study fills a gap in the South East literature by providing tested cost and performance data for sustainable material alternatives. Recommendations address skills training, material supply chain development, and inclusion of sustainable material cost data in professional estimating resources. Keywords: sustainable materials, residential construction, cost implications, South East Nigeria, earth blocks