Project – Effect of Construction Cost Inflation on Project Delivery in Selected Building Projects in Lagos State

CHAPTER ONE

1.1 Background to the Study

The construction industry plays an important role in economic development through the provision of residential buildings, commercial facilities, public infrastructure, and other structures required for social and economic activities. The successful delivery of building projects depends on effective planning, adequate financing, procurement of materials, coordination of labour, and control of project costs and time. However, the construction industry is particularly vulnerable to economic changes because building projects often require substantial financial commitments over extended periods. Changes in the prices of cement, reinforcement, roofing materials, finishing products, labour, transportation, and construction equipment can affect the financial viability of projects after contracts have been awarded. Dlakwa and Culpin (1990) identified fluctuations in material, labour, and plant costs, together with delays in payments, as important causes of cost overruns in Nigerian public-sector construction projects. This indicates that construction cost management requires continuous attention to changing economic conditions throughout the project lifecycle. Consequently, understanding the influence of construction cost inflation on project delivery is essential for improving the financial and operational performance of building projects.

Construction cost inflation refers to the sustained increase in the prices of materials, labour, equipment, transportation, and other resources required for construction activities. It may arise from general inflation in the economy, exchange-rate depreciation, increases in fuel prices, supply-chain disruptions, changes in taxation or government policies, and variations in demand for construction materials. In Nigeria, fluctuations in the exchange rate can affect the cost of imported building products and equipment, while increases in fuel prices can raise transportation and production expenses for both imported and locally manufactured materials. Akanni, Oke, and Omotilewa (2014), in their study of rising building-material costs in Lagos State, identified exchange-rate movements, fuel and power costs, and changes in government policies and legislation among the important factors associated with increasing construction costs. These findings show that construction cost inflation is influenced by both domestic and external economic conditions. For building projects, such increases may make original estimates inadequate, require additional financing, and force clients and contractors to reconsider procurement plans, construction methods, or project specifications.

The effect of construction cost inflation is particularly important in Lagos State because of the scale of building activity, demand for housing, commercial development, and competition for construction resources. Projects undertaken in the state may involve residential estates, private housing developments, commercial buildings, institutional facilities, and public-sector buildings. When the prices of essential materials rise after the preparation of a bill of quantities or the award of a contract, the original budget may no longer cover the cost of completing the work. Babalola, Aderogba, and Adetunji (2022), in their investigation of inflation and cost overruns in public-sector construction projects in Nigeria, collected evidence from public building projects in Lagos State and reported that inflation and cost overruns affected the projects examined. Similarly, Akanni et al. (2014) demonstrated that rising building-material costs have implications for construction activity in Lagos. These findings make Lagos State an appropriate setting for investigating how construction cost inflation affects the delivery of selected building projects and the measures used by project stakeholders to respond to cost increases.

One of the major consequences of construction cost inflation is the possibility of cost overruns. A cost overrun occurs when the final cost of a project exceeds its original budget or approved contract sum, although the causes may include factors beyond inflation alone. When material prices increase unexpectedly, contractors may find that the funds initially allocated for procurement and construction are insufficient. Depending on the contractual arrangements and availability of additional finance, this situation may result in requests for revised budgets, negotiations over contract variations, reduced profit margins, or disputes between clients and contractors. Babalola et al. (2022) examined the relationship between inflation and cost overruns in public-sector building projects in Nigeria and identified cost and project-delivery difficulties associated with inflationary conditions. Nnadi and Najjobyo (2025) also found that material-price fluctuations, inaccurate cost estimates, and payment delays can contribute to financial pressure and operational disruption in Nigerian construction projects. Therefore, assessing the influence of inflation on project delivery requires examining not only the increase in total project cost but also the processes through which changing prices affect budgets, procurement decisions, and the financial capacity of project participants.

Construction cost inflation can also affect project duration and the timely completion of building projects. When the cost of materials rises beyond the contractor’s financial capacity, procurement may be postponed, construction activities may be slowed, and work may be suspended while additional funds are secured. Contractors may also have difficulty maintaining the original construction programme when suppliers change prices frequently or when previously planned purchases become unaffordable. Aibinu and Jagboro (2002), in their study of the effects of construction delays in Nigeria, found that delays were associated with time and cost overruns and had significant implications for completion cost and time. Although delays can arise from several sources, inflation-related financing and procurement difficulties may intensify their effects. Diugwu et al. (2017), in their modelling of time overruns, inflation rates, and completion costs in Nigerian construction projects, also examined how inflation and project duration interact in determining the final cost of construction. These findings indicate that the influence of inflation should be evaluated in relation to both the financial and scheduling dimensions of project delivery.

Another important concern is the effect of inflation on construction quality and the ability of project stakeholders to maintain the original specifications. When the costs of materials and labour rise significantly, contractors may face pressure to reduce expenses, renegotiate specifications, substitute materials, or seek additional payments. If such decisions are not properly assessed and controlled, they may affect the quality, durability, and safety of the completed building. However, cost increases do not automatically result in poor quality; the outcome depends on the availability of finance, contractual provisions, procurement decisions, professional supervision, and quality-control procedures. Akanni et al. (2014) identified the implications of rising building-material costs for construction performance in Lagos State, while Nnadi and Najjobyo (2025) examined the financial and operational consequences of material-price volatility and cost-estimation inaccuracies in Nigerian construction projects. These studies underline the importance of investigating whether inflationary pressures affect the quality of work, the scope of projects, and compliance with contractual requirements in selected building projects in Lagos State.

Effective responses to construction cost inflation require reliable cost estimates, realistic contingencies, careful procurement planning, effective contract administration, and continuous monitoring of market conditions. Project stakeholders may use bulk purchasing, timely procurement, alternative materials that satisfy technical requirements, revised work programmes, and appropriate price-adjustment provisions to manage exposure to changing costs. Nevertheless, the suitability of these measures depends on project size, funding arrangements, contract type, material availability, and the timing and magnitude of price changes. Nnadi and Najjobyo (2025) emphasised the importance of improved cost-estimation methods, stakeholder communication, and stronger financial and contractual controls in managing construction cost risks. The findings of Aibinu and Jagboro (2002) also highlight the importance of improved project-management procedures in reducing the effects of delays. Against this background, the present study seeks to assess the effect of construction cost inflation on project delivery in selected building projects in Lagos State. It will examine the major inflationary factors, assess their effects on cost, time, and quality, and identify the strategies that may help construction stakeholders improve project delivery under changing economic conditions.

1.2 Statement of the Problem

Construction cost inflation presents a serious challenge to the effective delivery of building projects because increases in material, labour, transportation, and equipment costs can make original project budgets inadequate. In Lagos State, where residential, commercial, and public building projects require substantial investment, unexpected price increases can place pressure on clients, contractors, consultants, and suppliers. Contractors may experience difficulties purchasing materials at the rates anticipated during tender preparation, while clients may be required to provide additional funds to maintain the original scope of work. Akanni et al. (2014) identified exchange-rate movements, fuel and power costs, and government policy changes among the factors contributing to rising building-material costs in Lagos State. Babalola et al. (2022) also examined inflation-related cost overruns in public-sector building projects in Lagos. However, the extent to which these pressures affect the delivery of different selected building projects requires further assessment.

A second problem is that inflation-related cost increases can disrupt construction schedules when funds become insufficient to procure materials and maintain the planned pace of work. Contractors may delay purchases while awaiting funds, seek revised payment arrangements, or slow down construction activities to manage cash flow. Such interruptions may extend project duration and increase costs through additional labour, equipment, supervision, and site-maintenance expenses. Aibinu and Jagboro (2002) established that construction delays in Nigeria can contribute to time and cost overruns, while Diugwu et al. (2017) examined the relationship between inflation, time overruns, and completion costs. These studies demonstrate that cost and time performance are closely related. Nevertheless, the specific ways in which construction cost inflation affects procurement, work progress, and completion schedules in the selected building projects in Lagos State need to be investigated.

A further problem concerns the potential consequences of rising construction costs for project scope and quality. When the original budget cannot accommodate increases in the prices of essential materials and services, project participants may seek additional funding, revise the scope of work, change procurement arrangements, or substitute materials. Where changes are not properly evaluated and controlled, they may create disagreements, compromise the intended specifications, or affect the quality of the completed building. Akanni et al. (2014) examined the implications of rising building-material costs in Lagos, while Nnadi and Najjobyo (2025) identified material-price fluctuations and cost-estimation inaccuracies as important sources of financial and operational difficulty in Nigerian construction projects. However, the extent to which inflation affects project scope, quality control, and compliance with specifications in the selected projects requires empirical examination.

Finally, although construction professionals may use contingency allowances, early procurement, cost monitoring, alternative materials, and contractual price-adjustment provisions to manage inflation, the effectiveness of these measures may differ from one project to another. Differences in project financing, contract arrangements, procurement practices, and the ability of clients to make timely payments may influence how well stakeholders respond to changing prices. Babalola et al. (2022) documented inflation-related cost overruns in public building projects in Lagos State, while Nnadi and Najjobyo (2025) highlighted the importance of accurate cost estimation and financial and contractual controls. There is therefore a need for a focused assessment of selected building projects in Lagos State to establish the major sources of construction cost inflation, determine its effects on project cost, time, and quality, and identify the measures adopted to minimise its adverse effects. The study is intended to provide evidence that can support better project planning, cost management, and delivery performance.

1.3 Aim and Objectives of the Study

1.3.1 Aim of the Study

The aim of this study is to assess the effect of construction cost inflation on project delivery in selected building projects in Lagos State.

1.3.2 Objectives of the Study

The specific objectives are to:

1. Identify the major factors contributing to construction cost inflation in selected building projects in Lagos State.
2. Examine the effect of construction cost inflation on the cost and budget performance of the selected building projects.
3. Assess the effect of construction cost inflation on project duration, completion time, and quality of work in the selected building projects.
4. Identify the strategies adopted by construction professionals and project stakeholders to minimise the adverse effects of construction cost inflation on project delivery.

1.4 Research Questions

The study will be guided by the following research questions:

1. What are the major factors contributing to construction cost inflation in selected building projects in Lagos State?
2. What effect does construction cost inflation have on the cost and budget performance of the selected building projects?
3. What effect does construction cost inflation have on project duration, completion time, and quality of work in the selected building projects?
4. What strategies are adopted by construction professionals and project stakeholders to minimise the adverse effects of construction cost inflation on project delivery?

1.5 Research Hypothesis

The following null hypothesis will be tested at the 0.05 level of significance:

H₀: Construction cost inflation has no statistically significant effect on project delivery in selected building projects in Lagos State.

1.6 Significance of the Study

The findings of this study are expected to be useful to clients, contractors, quantity surveyors, project managers, architects, engineers, policymakers, and researchers in the construction industry.

Clients and project owners: The study may help clients understand the financial and operational risks associated with rising construction costs. Its findings may support realistic budgeting, appropriate contingency planning, and timely financial decisions during project execution.

Contractors: The study may assist contractors in identifying the major sources of cost inflation and their implications for procurement, cash flow, construction schedules, and profit margins. It may also help contractors improve cost monitoring and procurement planning.

Quantity surveyors and cost consultants: The findings may provide useful information for preparing cost estimates, monitoring price movements, evaluating variations, and advising clients on appropriate cost-control measures. The study may also support the use of realistic contingencies and improved cost forecasting.

Project managers: The study may help project managers understand how inflationary pressures can affect the relationship between project cost, time, scope, and quality. The findings may assist in developing risk-management measures and adjusting work programmes when necessary.

Architects and engineers: The study may provide insight into how cost pressures influence material selection, design decisions, construction methods, and quality control. It may encourage consideration of technically appropriate and cost-effective alternatives without compromising building safety or performance.

Government and policymakers: The findings may contribute to policy discussions on construction-sector stability, building-material supply, procurement practices, and public-project budgeting. They may also help identify areas where improved economic planning and contractual guidance could support project delivery.

Researchers and students: The study may contribute to literature on construction economics, cost management, inflation, and project performance in Nigeria. It may also provide a foundation for future studies comparing public and private building projects or examining specific inflation-management strategies.

1.7 Scope of the Study

The study focuses on the effect of construction cost inflation on project delivery in selected building projects in Lagos State, Nigeria. Its content scope covers the causes of construction cost inflation, including material-price increases, exchange-rate movements, fuel and transportation costs, labour costs, and other relevant economic factors.

The study will examine the effects of construction cost inflation on project cost and budget performance, project duration and completion time, project scope, and quality of work. It will also investigate the measures adopted by clients, contractors, quantity surveyors, and project managers to manage inflation-related risks.

The geographical scope is limited to selected building projects in Lagos State. Respondents may include construction professionals and other stakeholders directly involved in the planning, costing, procurement, supervision, or execution of the selected projects. The findings will be interpreted in relation to the projects investigated and will not automatically be generalised to all construction projects in Nigeria.

1.8 Operational Definition of Terms

Construction cost inflation: A sustained increase in the prices of construction materials, labour, equipment, transportation, and other resources required to execute building projects.

Project delivery: The process of completing and handing over a building project in accordance with its agreed requirements for cost, time, scope, quality, and performance.

Building project: A planned construction activity involving the erection, alteration, extension, or renovation of a building.

Cost overrun: The amount by which the actual or final cost of a project exceeds its approved budget or original estimated cost.

Cost performance: The extent to which project expenditure remains within the approved budget or agreed financial limits.

Time overrun: The extension of a project’s completion period beyond its planned or contractually agreed duration.

Building materials: Physical resources used in construction, including cement, reinforcement, sand, aggregates, blocks, roofing products, timber, glass, and finishing materials.

Project scope: The agreed work, deliverables, specifications, and requirements that a building project is expected to complete.

Quality of work: The extent to which construction activities, materials, and completed work conform to approved specifications, applicable standards, and contractual requirements.

Cost-control measures: Procedures used to monitor, regulate, and manage project expenditure to minimise unnecessary costs and maintain budget performance.

Inflation-management strategies: Measures used by construction stakeholders to anticipate, absorb, or reduce the adverse effects of rising construction costs on project execution.

Price escalation: An increase in the price of materials, labour, equipment, or other construction inputs during a specified period.

Project – Effect of Construction Cost Inflation on Project Delivery in Selected Building Projects in Lagos State