Key Dimensions of Discrepancy between Approved Design and Actual Implementation in Addis Ababa Private Residential Construction Projects: Cause, Effect and Mitigation Strategies

Abstract

Approved designs serve as blueprints to guide project execution and ensure that the final structure fits the clients' needs and regulatory criteria. However, discrepancies between approved designs and actual implementation often arise during construction, resulting in a range of negative implications for project stakeholders. The study aims to investigate the cause and effects of the gap between approved designs and their actual implementation and developing strategies to minimize implementation gap on private residential construction projects in Addis Ababa. The specific objectives include identifying the causes of variance, to assess the legal and quality impacts of discrepancies, and to developing effective strategies and best practices to minimize the gap between approved designs and actual implementation in order to improve project outcomes and efficiency. To achieve these objectives, the study would employ a quantitative research approach. Data are acquired by using a questionnaire. The research design was used a descriptive research design; a stratified sampling and simple random sampling technique was use. The data analysis methods would use descriptive analysis techniques using fuzzy TOPSIS technique. The study outcomes revealed the main causes are poor communication among stakeholders (CC value 1.0); design changes (CC value 0.795); lack of strict enforcement (CC value 0.777); inadequate project planning (CC value 0.598); and shortage or poor quality (CC value 0.598). Addressing these dominant causes of variance requires a multifaceted approach that emphasizes communication, change management, regulatory compliance, thorough planning, and material quality assurance. The discrepancies between approved designs and actual implementations in residential construction projects in Addis Ababa have far-reaching impacts that compromise safety (CC value 1.0), structural integrity (CC value 0.91), quality (CC value 0.74), legal compliance (CC value 0.73), and durability (CC value 0.72) . Addressing these discrepancies through better oversight, adherence to regulations, and quality control measures is essential to ensure safe and sustainable construction practices in the region. The study outcomes also revealed that, effective strategies and best practices for minimizing the gap between approved designs and actual implementation in construction projects, with the aim of improving project outcomes and enhancing efficiency. The key findings emphasize the importance of a proactive and multifaceted approach, including: strengthening and consistently enforcing building codes and regulations (CC value 1.0), promoting and ensuring the use of quality and certified building materials (CC value 0.80), mandating and enforcing comprehensive on-site supervision (CC value 0.76), conducting regular quality control and quality assurance inspections (CC value 0.73), and establishing a formal change management process for client requests (CC value 0.52). These strategies promote accountability, transparency, and proactive risk management throughout the construction lifecycle, fostering a culture of quality and compliance that leads to safer, more functional, and more sustainable buildings.