Assessing The Impact of Design Errors in Construction Project in Selected Construction Companies in Lagos State
Introduction
Design errors in construction project environments remain one of the most persistent and costly challenges facing the global building industry, and a 2025 study from Lagos State University offers some of the clearest quantitative evidence yet on just how severe the problem truly is. Conducted by researchers Oladele Waheed Olatunji, Oshin Idris Ibidapo, and Lawal Yusuf Adedayo, the study — published in the International Journal of Research and Innovation in Social Science (IJRISS) — examined how these errors drive up final costs, trigger budget overruns, and generate unexpected expenses across ten leading construction firms in Lagos State, Nigeria.
Lagos is the economic engine of Nigeria's construction sector, an industry valued at approximately $140 billion in 2023 and projected to grow at an average annual rate of 3% through 2029. With the state contributing between 15% and 30% of the nation's GDP, any factor that undermines project efficiency carries enormous economic consequences. This reality makes understanding design errors in construction project workflows not merely an academic exercise but a pressing policy priority for both public and private stakeholders.Why Design Errors in Construction Project Delivery Demand Urgent Attention
The researchers define a design error as a deviation from accuracy, correctness, or generally accepted professional practice. These errors fall into three broad categories: imperfections (minor deviations with little impact on cost or time), non-conformance errors (failures to meet specifications that require corrective action), and omissions. While imperfections may go unrecorded and appear only in as-built drawings, non-conformance errors and omissions can cascade into rework, schedule delays, contractual disputes, and even total project abandonment.
The study's literature review draws on a broad body of international research to show that the consequences of design errors in construction projects extend far beyond the drawing board. They manifest as defective work, material waste, contractual disagreements, change orders, and incomplete documentation — all of which inflate budgets and erode stakeholder trust.
The researchers note that when construction documents are error-free, the reputation of participating consultants improves, and the costly challenges of redesigning and fixing problems are largely eliminated.
Methodology: How the Lagos State Study Was Conducted
The research team collected primary data through structured questionnaires distributed to 120 professionals across ten top construction companies in Lagos State, including Cappa and D'Alberto Plc, ITB Nigeria, El-Alan Construction Company Ltd, and Cavalli Project Limited. Respondents included project managers, project supervisors, technical staff, and administrative personnel. Of the 120 questionnaires distributed, 117 were returned and analyzed — a response rate of 97.5%.
Data reliability was confirmed using Cronbach's Alpha, which yielded a score of 0.807, well above the accepted threshold of 0.70. The researchers employed both descriptive statistics (percentages, means, and standard deviations) and inferential statistics (regression analysis) using SPSS version 26 to evaluate the impact of design errors in construction project outcomes across three dependent variables: final cost, cost overrun, and additional cost.
Key Statistical Findings
Impact on Final Project Cost
The regression analysis revealed a moderate positive relationship between design errors and final project costs, with a correlation coefficient (R) of 0.515. The R-squared value of 0.389 indicates that approximately 38.9% of the variation in a project's final cost can be explained by the presence and severity of design errors in construction project phases. The regression equation derived from the data is:
Final Cost = 2.468 + 0.227 × Design Error
This means that for every one-unit increase in design errors, the final project cost rises by 0.227 units — a relationship confirmed as statistically significant with a t-value of 3.563 and a p-value of 0.000.
Impact on Cost Overruns
The most striking finding relates to cost overruns. The correlation coefficient of 0.650 signals a strong positive relationship, and the R-squared value of 0.423 demonstrates that 42.3% of the variation in cost overruns is attributable to design errors in construction project execution. The regression equation is:
Cost Overrun = 1.692 + 0.470 × Design Error
With a t-value of 9.176 and a p-value of 0.000, this is the strongest statistical relationship identified in the entire study, underscoring that design-phase mistakes are a primary driver of budget escalation across Lagos State's construction sector.
Impact on Additional Costs
The third regression model examined additional costs arising from unforeseen expenses, scope changes, and rework. The R-squared value of 0.396 shows that 39.6% of the variation in additional costs is explained by design errors in construction project documentation and delivery. The equation is:
Additional Cost = 1.968 + 0.385 × Design Error
Again, the relationship is statistically significant (p = 0.000), confirming that errors originating in the design phase generate measurable downstream financial burdens that can, in severe cases, lead to project abandonment.
Who Bears Responsibility?
The survey results paint a nuanced picture of accountability. A significant majority of respondents — 67.5% — strongly agreed that designers are primarily responsible for design errors in construction project deliverables. However, 65% also agreed that project owners, designers, and contractors share collective responsibility. Notably, 66.1% strongly disagreed that project owners alone are to blame, suggesting that the industry views this as a shared systemic problem rather than an individual failing.
When it comes to the financial consequences, respondents indicated that all three parties — clients (67.5% agreement), designers (72.6% agreement), and contractors (67.5% agreement) — bear accountability for the additional costs generated by these errors.
Major Contributing Factors
The study identified several key drivers behind design errors in construction project workflows in Lagos State:
- Unclear scope of work: 96.6% of respondents agreed or strongly agreed that an ill-defined project scope is a major contributing factor.
- Time pressure: 95.8% acknowledged that inadequate time allocated to the design phase leads to mistakes.
- Poor funding: A full 100% of respondents agreed or strongly agreed that insufficient project funding contributes to errors.
- Inexperienced designers: 99.1% confirmed that the absence of experienced design professionals increases the likelihood of errors.
- Technology gaps: 97.4% agreed that the implementation of Computer-Aided Design (CAD) software has helped reduce the frequency of design errors in construction project documentation, implying that firms lacking such tools remain at significantly higher risk.
Policy Recommendations
The researchers propose a series of actionable recommendations for government agencies, professional bodies, and construction firms:
- Mandated design reviews: The Lagos State Building Control Agency (LASBCA) should require staged design reviews before issuing building permits, with compliance monitored rigorously.
- BIM adoption incentives: Government-backed grants and tax incentives should be offered to firms investing in Building Information Modelling (BIM) tools and staff training, with a certification scheme established under the Nigerian Institute of Quantity Surveyors (NIQS) and the Nigerian Building and Road Research Institute (NBRRI).
- Risk Assessment Methodologies (RAM): Standard FIDIC-based contract templates should incorporate RAM requirements, with LASBCA auditing submitted assessments before project approval.
- Digital scope documentation: The Ministry of Physical Planning and Urban Development should issue centralized digital templates and make comprehensive scope documentation a precondition for design approval.
- Quality-Based Selection (QBS): Public procurement guidelines should be revised to mandate QBS criteria for design contracts exceeding a fixed budget threshold, reducing the temptation to prioritize low-cost bids over design quality.
Conclusion
The evidence from this 2025 Lagos State study is unambiguous: design errors in construction project environments are not minor inconveniences but major financial and structural risks that account for up to 42.3% of cost overrun variation. As Nigeria's construction sector continues its projected growth trajectory, the cost of inaction will only escalate.
The study's recommendations — from mandated design reviews and BIM adoption to improved scope documentation and quality-based procurement — offer a practical roadmap for stakeholders at every level of the industry.
For researchers, policymakers, and construction professionals worldwide, this research serves as a compelling reminder that investing in design-phase accuracy is not an overhead expense but a fundamental safeguard against project failure. Addressing design errors in construction project pipelines is, ultimately, an investment in the built environment's safety, sustainability, and long-term economic viability.