A triple bottom line sustainability performance index in engineering construction: evidence from Uganda

Abstract

Using the Triple Bottom Line (TBL) framework, this research designed a contextually relevant Sustainability Performance Index (SPI) to evaluate engineering construction practice in developing countries. Construction is increasingly seen as a complex business involving environmental, social, and economic challenges. The study employs a quantitative approach, collecting data from 290 stakeholders via structured questionnaires. Secondary sources, interviews and field observations informed the identification and contextualization of sustainability variables within the Ugandan construction sector. The key sustainability variables are found, ranked and modelled using analytical techniques such as the Relative Importance Index (RII), Spearman’s correlation, and multiple regression analysis. The findings show that environmental issues—specifically waste management, energy efficiency, and emissions control are the most influential drivers of sustainability performance. Social drivers, such as health and safety, stakeholder engagement and skills development, also make a vital contribution. All the while, the economy, while critical, favours the quick win of saving money in the short term over long-term sustainability. The positive correlation among TBL dimensions strongly indicates their interdependence. A 64% of the variance of sustainable construction practices is explained by the regression model, indicating a moderately good predictive power. The resulting SPI combines these weighted indicators into a composite index, reinforced by a practical scorecard that facilitates the classification of performance indicators. It provides a data-enabled, policy-focused framework for evidence-based sustainable construction practices, enabling decision-making in developing countries.