Building- Conference Papers

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    Open Access
    An alternative sustainable walling material for building projects in construction industry
    (ASOCSA2023, 2023) Oladiran O.J.; Anugwo I.C.; Simeon D.R.
    Purpose Autoclaved Aerated Concrete (AAC) is an eco-friendly and sustainable material. This study evaluates the acceptability and key drivers as a walling material. Design methodology Seventeen online questionnaires were sent via email to South African construction practitioners in five provinces and 99 questionnaires self-administered to construction professionals in Lagos, Nigeria. The statistical techniques used for analyses were frequency distribution, percentages, ranking, mean score and percentage mean unit. Findings The top four AAC block types used in building projects in South Africa are those AAC made using Ordinary Portland Cement (OPC) of grade 52.5, OPC of grade 42.5, Aluminum Powder (AP) or Rice Husk Ash (RHA), and Palm Oil Fuel Ash (POFA) or Pulverized Fuel Ash (PFA). The top factors influencing the use of AAC in Nigeria are its lightweight characteristics, ecological improvements, energy efficiency, adaptation to hot regions, excellent heat assimilation characteristics, good fire resistance, and adaptability to architectural flairs. Whereas, AAC is mostly used in South Africa due to its outstanding fire insulation properties, lightweight characteristics, energy efficiency, superior thermal absorption characteristics, adaptability to any type of architecture, eco-friendliness; and remarkable thermal conductivity. Research implications The research draws the conclusion that AAC block producers that manufacture AAC variations outside the four listed above would probably not grow in business since they would receive little support from construction practitioners. Practical implications Although lightweight characteristics is the most important driver for both nations, the relevance of drivers for the use of AAC blocks varies. This suggests that practitioners in both nations prioritize the block's lightweight properties, which could be preferred for tall projects due to lower costs for the foundation and other structural components.
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    Open Access
    Assessment of Factors Affecting Maintenance Management of Public Hospital Buildings in Lagos State, Nigeria
    (RICS, Georgia tech publishers, 2007) Adenuga, O. A.; Odusami, K. T.; Faremi, J. O.
    The study focused on factors affecting maintenance management of public hospital buildings in Lagos state. It also assessed the operational state of public hospital buildings within the study area. In achieving these objectives, opinions of maintenance officers and users of selected public hospital buildings were sampled through structured questionnaires. The data collected were analyzed using descriptive and inferential statistics. The analysis revealed the operational state of public hospital buildings in Lagos State as been average, and there is no significant difference in the perception of the maintenance staff and the users as to the operational state. Maintenance officers and users of the buildings both ranked insufficiency of fund for maintenance programme as second most significant factor among other factors responsible for poor maintenance management of our public hospital buildings. Other factors found to be highly significant by the maintenance officers are; attitude of users and misuse of facilities, lack of discernible maintenance culture, inadequate training and reluctance of some establishment to support innovations. The users on their own perspective, ranked the inflation of cost of maintenance by the operatives, use of poor quality components and materials by the maintenance department and without long-term arrangements for the supply of essential parts for replacement as the most significant factor affecting maintenance management respectively. The study recommended proactive measures to reduce the occurrence of defects in the buildings elements and services. Governments are to provide adequate funding for the running of public hospitals and it should be a government policy that every hospital either public or private must have maintenance policy guiding the implementation of their maintenance programme. Building elements should be regularly inspected to ensure their functionality.
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    Open Access
    Assessment of Risks Associated with The Procurement of Facilities Management Services in Nigeria
    (CIB W107 2014 International Conference, 2014) Faremi, J.O; Adenuga, O.A; John, I.B; Akinbode, A.T
    Facilities management (FM) services can be managed in-house, outsourced or partly in house and partly outsourced (Hybrid). Each of the FM procurement options possesses inherent risks of grave consequences. This study aim at assessing risks inherent in each of the procurement options for FM services. A structured questionnaire was used as the principal instrument for this study. 75 copies of structured questionnaires were distributed, 55 were completed and returned representing 73% response rate. Data for the study was processed and analysed using SPSS for both descriptive and inferential statistics. The analysis revealed risks with the highest level of potential occurrence in in-sourcing FM services as low labour productivity, overstaffing and poor accountability. While, threat to data security, loss of management controls and poor motivation are major risks in outsourcing FM services. This studv concludes that poor accountability and loll' labour productivity are major risk factors that cuts across all FM procurement routes that is capable of affecting employees' relationship and passion for work. Performance reward and regular account reconciliation are therefore recommended since this can either reinforce an outsourcing relationship or enhance an in-house retaining of FM services.
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    Open Access
    Assessment of the Correlation between the Quality of Building Materials and Strength of Concrete Members in the Building
    (International Journal of Applied Engineering Research, 2018-03) Ogunde, Ayodeji, O.; Egbanubi, kehinde, C.; Ameh, John , O.; OPeyemi, Joshua
    The constituents of concrete have a significant amount of influence on the strength of concrete. Consequently, this research work addressed the use of compressive strength test to determine concrete strength. To achieve the aim, experiments were carried out on three different aggregate sizes-19mm, 16mm, and 13.2mm. The results showed the silt percent contained in each tested aggregate, 3% for fine aggregate, 1% for 13.2mm aggregate, and 0.05% for both 16mm and 19mm aggregate size. It also showed the moisture percent contained in the fine aggregate sample was 2.56%, the workability of the tested concrete of mix ratio1: 1 1 2 2 was 0.95, the Impact Value (toughness) of the aggregates; 9.01% for the 13.2mm size, 7.13% for the 16mm, and 7.95% for the 19mm size of aggregate. The compressive strength test showed that the 19mm size aggregate had the highest strength after each seven days. For the test on concrete members (column), Schmidt hammer test was carried out to determine the strength and variation in the workmanship of each tested column. The result of this research work showed that the 19mm aggregate had the most strength; and that the aggregate sizes influence the strength of the concrete. The research also showed that for each concrete member there is high variation in strength due to variation in workmanship. It is recommended that columns should be tested periodically for variation in strength to avoid building collapse.
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    Open Access
    Assessment of the Determinant Factors of Do-It-Yourself (DIY) Maintenance Approaches to Housing: A Perspective of Owner-occupiers and Tenants
    (2011-09) Abisuga, O.; Adenuga, O.; Farinloye, O.
    The study assessed the practice of do-it-yourself (DIY) maintenance as a means of improving housing stock in Lagos state. The study identified the factors influencing and militating against the practice. In achieving the set objectives, the study adopted research survey technique. A total of 300 questionnaires comprising 160 for owner-occupiers and 140 for tenants were administered for the study. The population was selected from fifteen (15) local government areas in Lagos state, based on stratified random sampling technique. Data collected were analysed using descriptive and inferential statistics. The findings of the study revealed that the factors influencing the practice of do-it-yourself (DIY) maintenance are; to provide a habitable environment, to retain the performance of facilities amongst others while the factors militating against the practice are; jobs involving special skills, health and safety issues, lack of technical know-how amongst others. The hypotheses postulated reveal that there is an association between the factors influencing the practice of do-it yourself (DIY) maintenance by the owner-occupiers and the tenants. There is also an agreement between the factors militating against the practice as perceived by the owner-occupiers and the tenants. Based on the findings, the study recommends vocational training for building users, building products should be user’s friendly, provision of DIY manual for products and tools that will facilitate the practice amongst others.
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    Open Access
    CAUSES AND MINIMIZATION STRATEGIES OF WASTAGES IN SELECTED BUILDING MATERIALS
    (Nelson Mandela Metropolitan University, Gqeberha, South Africa, 2012) Oladiran O.J.
    Materials wastage is a common feature in many building sites and poses great challenges to the construction industry globally. Some materials are known for their high level of waste incidence from one site to the other. Cement, concrete, timber and steel are materials that account for over 50% of the cost of materials in any project. It is opined that a reduction in the wastages of these specific materials will result to low construction cost amongst other benefits. This study investigates the causes and minimization strategies of wastage in these four materials on building sites in Nigeria. The population of the study is construction professionals in organizations in Lagos State, Nigeria. The survey research involves the use of a questionnaire administered via convenience sampling techniques, which resulted to a sample size of 31. Descriptive and inferential statistics tools are used for the analysis. The study reveals that improper storage contributes most to cement, timber and steel wastages while that of concrete is improper batching. Good storage, purchase of good quality cement, ordering required quantity and proper bagging were highlighted for minimizing cement wastage. The study recommends usage of the strategies discovered in this study to curb wastage incidence.
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    Open Access
    Causes And Minimization Techniques Of Materials Waste In Nigerian Construction Process.
    (Fifth International Conference on Construction in the 21st Century (CITC-V), Turkey, 2009) Oladiran O.J.
    A major characteristic of average construction sites in Nigeria is the presence waste materials in various forms and large quantities. This culminates to inter alia, high construction costs and great hindrance to affordability of good houses to the citizens. In this regard, a survey research was embarked on; it focuses on identifying the causes of materials waste incidence and their various minimization techniques in Nigerian construction process. The population of the study is the construction professionals in selected firms in Nigeria. It involves the usage of a designed questionnaire administered via convenience sampling technique. Certain predetermined causes coined from literatures are included in the questionnaire while open-ended questions are employed to elicit the actual materials waste minimization techniques in the firms. Descriptive statistics tools are used to analyze the data. The study reveals causes of materials waste as: uneconomical shape of materials and components due to design; building failure/defects; workers’ mistakes; theft; vandalism; inconclusive specifications; estimators’ errors; ineffective communication; unfamiliarity with alternative products; design changes; lack of proper supervision; loading and unloading of materials; various forms of materials’ packaging; substandard materials; poor site layout; misinterpretation of drawings; poor site conditions; setting out errors; and improper transportation of materials. It also sheds light on the materials waste minimization techniques as: materials inspections on arrival on sites; documentations of materials in and outflows; adherence to design details; effective communications; good transportation systems for materials; good storage facilities; training of storekeepers/site personnel; reuse of materials; daily stock taking; usage of materials requisition booklets; ensuring sub-soil investigations before projects commence; and regular site meetings. Conclusions are made based on these findings in the study. However, the study recommends that practitioners should employ all the techniques discovered in the study to minimize materials waste in their projects. This study will therefore contribute to materials waste minimization both in Nigerian and global construction processes.
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    Open Access
    CONSTRUCTION PROFESSIONALS’ PERCEPTION ON THE AWARENESS, APPLICATION AND BENEFITS OF MATERIAL WASTE MEASUREMENT TECHNIQUES IN NIGERIA.
    (CIB, 2014) Oladiran O.J.
    Several studies have been done on materials waste management all geared towards pinpointing waste origins and minimization processes. It has been opined that waste quantities need to be determined before attempting to minimize materials wastage. Accurate determination of materials waste quantities depend largely on the techniques and methods employed for its quantification. This study investigates Material Waste Measurement Techniques (MWMT) among professionals in the Nigerian construction industry. The objectives are to investigate the awareness and usage of MWMT, factors that hinder their application, the impact of the techniques on construction cost and their benefits. The population of the study is construction professionals in construction organizations and convenience sampling technique was used to draw a sample size of 60. Descriptive statistics tools were used to analyze the data. The study sheds light that component index has the highest impact on construction cost; non-challant attitudes of contractors towards waste is topmost among the factors that hinders the usage of MWMT ; while determination of actual amount of materials wastage is the chief benefits of MWMT. The study recommends improvement in the usage of MWMT to determine waste volume of construction projects in Nigeria. The study will contribute significantly to the management of materials wastages on construction projects.
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    Open Access
    CONTROL MEASURES OF ACCIDENTS: NIGERIAN BUILDING PROJECTS’ CASE.
    (Proceedings of CIB-2008-Transformation through Construction, Dubai., 2008) Oladiran O.J.; Ogunsanmi O.E.; Soyngbe A.A.
    This study explores the various safety and control measures (SCM) of accidents in building projects to minimize accidents’ occurrence and consequent waste generation. A research methodology, consisting of a literature review and a field study were used to achieve the research objectives. The field survey involves a designed questionnaire that was administered through convenience sampling technique within Lagos State and descriptive analysis tools were used for the analysis. The field survey reveals different control measures in place and their rate of usage on building projects. On the other hand, the literature survey sheds light on the types of accidents on building projects and their respective control measures with methodologies for accidents’ preventions. Reccomendations based on the findings of the two surveys are outlined in the paper.
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    Open Access
    Effects of contract planning on project performance.
    (Faculty of Environmental Sciences, University of Lagos., 2020) Oladiran O.J.; Musa V.S.
    Construction projects suffer poor performance due to certain causes, such as inefficiencies, though its root cause is lack of adequate contract planning in the execution of construction projects. On the basis of the huge cost usually invested into construction and the need for project failure to be addressed to enhance sustainability, the problem that this study seeks to solve is poor project outcomes due to improper planning. This study investigated the effect of contract planning on project performance. The specific objectives are to identify the types of contracts frequently adopted in construction projects, to establish the relationship between contract planning and project performance, and to evaluate the challenges of contract planning in construction projects. The population of the study is construction professionals (i.e. architects, builders, quantity surveyors and engineers) in Lagos State. A total of 150 questionnaires were administered to the respondents. The respondents were purposively selected from the population. Frequency, percentage and mean were used to analyse the data. The findings reveal that several types of contract are adopted on construction projects, including traditional, management, integrated among others. Contract planning also contributes positively to project performance, especially in the aspect of quality, cost, time, functionality and minimization of rework, thereby fostering sustainability in construction projects. It is concluded that although there are various types of contract, they are adopted differently on specific projects. It implies that the type of project could determine the type of contract to be adopted. Additionally, certain challenges must be addressed for contract planning to achieve sustainability and other intentions on construction projects. It is recommended that increased attention should be drawn towards the less frequently adopted contracts. This can be done via seminars, conferences, and other training programs. Measures for contract planning to achieve sustainability in construction projects must also be initiated by construction organizations and institutions.
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    Open Access
    ESSENTIAL SKILLS FOR MAINTENANCE MANAGERS IN PUBLIC HOSPITAL BUILT ENVIRONMENT: NIGERIA CASE STUDY.
    (Royal Institute of Chartered Surveyors, 2008) Adenuga O.A.; Odusami K.T.; Oladiran O.J.; Farinloye O.O.
    The research investigated the maintenance management practice in public hospital buildings in South-west, Nigeria, and in the process, identified the essential skills for maintenance managers in a hospital built environment and users satisfaction with the maintenance work. A total of 552 questionnaires comprising 206 for maintenance staff and 346 for users of public hospital building were collected and used for study. The survey covered 46 public hospitals representing 40% of the total number of existing public hospitals in South-west, Nigeria. The study comprises all the 11 federal owned hospitals and 35-selected state owned in South-west, Nigeria based on stratified random sampling technique. Data collected were analysed using mean item score, and spear-rank correlation coefficient. Findings of the study revealed that in public hospitals in South- west, Nigeria, the staff strength of the maintenance departments is inadequate and the maintenance staffs are inexperience on hospital maintenance management. Majority of the users of public hospital buildings do not have access to any formal training on effective use of hospital facilities. The most important skills considered necessary for an effective maintenance manager in executing maintenance operations in public hospitals according to the study are professional experience, intelligence, good communication, good qualification and human relation skill. Based on the above findings, the study recommends that management should ensure that the head of maintenance department has the required maintenance managers’ attitude success factors before appointing them rather than being political in their selection. Management should ensure that both the management and all the staffs are given adequate training for effective use of the building and the services.
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    Open Access
    Ethical Decision Making as a Driver for Change in Health and Safety (H&S) in the Nigerian Construction Industry: A Strategy for the next Decade
    (2015-11-30) Kukoyi, P.O.; Smallwood, J.
    The construction industry is known for its poor H&S record. This record has been linked to non-compliance with H&S requirements on construction sites. In a developing country such as Nigeria, inadequate statutory laws and regulations have exacerbated the situation. Thus, adoption of ethics could ameliorate the poor H&S performance within the construction industry. A state-of-the-art review of literature was conducted, the selection criteria focused on studies addressing ethical decision making in H&S practices in construction-related literature. The findings indicate that studies focused on ethical decisions in H&S practice in the construction industry are limited. Based on the review of literature, it is evident that ethical decisions can improve social responsibility and H&S performance in the construction industry. The trends and gaps can also serve as a motivation for future studies aimed at promoting a healthier and safer construction environment
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    Open Access
    Ethical ideology and Nigerian building professionals’ ambivalence toward ethical issues
    (London South Bank University, 2018-11) Ameh, John , O.
    Consensus is that corruption and other ethical lapses are prevalent in the construction industry. Professional ethical lapses often lead to huge economic loss in the form of additional cost of projects, rework engendered by poor quality of works, frequent maintenance management of buildings, and in extreme cases collapse of building. Ethical ideology accounts for variation in individuals’ perception about moral issues and consequent behaviour notwithstanding existence of professional code of conduct. The purpose of this study is to examine the dimensions of ethical lapses within the Nigerian building industry, and also investigate factors that influence professionals’ ultimate decision to engage or refrain from ethically questionable behaviour in the procurement of building project. The study methodology involves cross-sectional survey of key built environment professionals in consulting, contracting and client organisations. The findings will form needed benchmark for resolving ethical issues in the building industry in developed and developing countries.
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    Open Access
    FACTORS AFFECTING MAINTENANCE COST OF INSTITUTIONAL BUILDINGS
    (2014) Faremi, Julius Olajide; Adenuga, Olumide; John, Iniobong Beauty
    Building maintenance management in institutions and organisations with sizeable building assets is a complex and multi-faceted process that involves planning, directing, controlling and organizing resources for the sustenance of the building’s physical, functional and operational performance. The purpose of this research work is to propose ways of optimizing maintenance expenditure of institutional buildings in Nigeria. Based on review of literatures, factors impacting maintenance costs were categorized into four categories comprising of; building characteristics, political factors, technical and administrative factors respectively. A questionnaire survey of maintenance departments’ staff of tertiary institutions in Lagos State was conducted and the data were analyzed using the statistical packages for social science (SPSS). The study reveals the predominant factors affecting maintenance costs of institution buildings to include; age, floor area and vertical spread of buildings, poor building designs, improper coordination of incorporated building services and deferred maintenance. The study recommends a review of maintenance policies for institutional buildings with a view to equipping the maintenance organisations with competent hands and skilled personnel to handle maintenance activities of critical systems and services in institution buildings.
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    Open Access
    FACTORS INFLUENCING BUILDING MAINTENANCE SOURCING DECISION IN NIGERIA SOUTHWEST UNIVERSITIES
    (University of Lagos, 2018-08-28) Faremi, O.J; Adenuga, O; John, B.I; Adegoriola, M; Muraina, A.O
    Appropriate decision making on either to insource or outsource maintenance services in universities is a strategic task. Such a decision-making process is usually complex and challenging. Insourcing maintenance services, different sourcing option suits different maintenance scenarios, hence the need to study the factors influencing decision to insource or outsource maintenance services in any particular organisation or institution. Through a crosssectional survey, data were gathered from 112 respondents comprising a census of 28 maintenance managers and purposive sampling of 84 maintenance technical staff. The relative influence index and the Welch‘s test were employed as statistical tools for data analysis. The results indicate that factors influencing insourcing of maintenance services in universities include: the development of in-house maintenance staff, technological requirements uncertainty and the difficulty in getting trustworthy contractors. Factors influencing building maintenance outsourcing decision in universities include the need for specialised expertise, strategic alliance with contractors and the need for specialised management. The results of the Welch‘s ANOVA F (2, 87) =3.50, p=0.17 and F (2, 92) =2.08, p=0.26, showed that there was no significant difference in the factors influencing insourcing and outsourcing decisions across federal, state and private universities respectively. The study concludes that insourcing decision is influenced by management factors while outsourcing decision are influenced by strategic and technological factors.
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    Open Access
    Government policies in the construction industry: awareness, application and effects.
    (Australasian Universities Building Education Association (AUBEA), 2023) Oladiran O.J.; Okonkwo C.; Komolafe T.A.
    The construction industry in developing countries is faced with many challenges affecting its output and appears to be lagging in improved project outcomes. Governments influence the industry’s productivity and performance via monetary and fiscal policies. The aim of this study is to examine the effects of government policies on construction projects, with the view to improving project outcomes. The objectives of the study is to examine the level of awareness and application of government policies; and the effect of government policies on construction project outcomes. The population of the study was construction professionals in Lagos, Nigeria. The study reveals that devaluation of the Naira, Nigerian currency, is the government policy that the respondents are mostly aware; other government policies with high level of awareness include but not limited to: increase in import duties, high taxation and increased government spending. The study concludes that government policies have the highest effect on cost performance of construction projects. It implies that good government policies could lessen construction cost and improve affordability of housing. The study recommends that awareness among construction professionals on government policies should be improved. This can be done by professional bodies and associations embarking on enlightenment seminars and workshops to intimate construction professionals on the government policies available within the construction industry and their resultant effects to companies and other stakeholders.
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    Open Access
    Human Resource Management in the Nigerian Construction Firms: Practices and Challenges
    (Journal of Construction Business and Management, 2017-07-13) Ameh, John , O.; Daniel, Emmanuel, I
    Improvement on human resource management is critical to overall productivity and cost effectiveness in the construction industry. This study assesses the current human resource management practices in the Nigerian construction organisation and the challenges confronting it. Questionnaire survey was adopted for data collection while the sampling technique was purposive. Ninety eight human resource managers and construction professionals in two categories of construction organisations (client organisations involved in housing development and contractor organisations) were sampled. The results reveal that due process was followed in the recruitment process but the selections of desired candidates were often hampered by interferences and competitive work conditions. Furthermore, training and development practices were superficial, involving orienting newly recruited employee on facilities for optimum performance rather than developing employee job related competences. Provision of appropriate/modern working tools and equipment and provision of incentives and benefits to staff were the prevailing motivation and labour union practices. Challenges facing human resource management practice in the Nigerian construction industry include high labour turnover, interference at the selection stage, competitive wages and compensation issues among others. Further research is required to assess the impact of identified human resource practices on productivity and project performance.
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    Open Access
    IMPLEMENTATION OF WASTE MANAGEMENT PLAN:IMPORTANCE, CONTENTS, PROCEDURES, PROBLEMS AND SOLUTIONS.
    (AEC, 2010) Oladiran O.J.
    Waste management plan (WMP) is an innovative approach for waste minimization. Its usage in Nigerian projects is not rampant and with little benefits. The concept and practice of WMP is not detailed and elaborate in Nigeria as in some developed countries such as USA and UK. An inquiry into the concept and procedures for implementation of WMP in selected countries will be beneficial to construction projects in Nigeria and like countries. This research proposes to identify the various problems associated with the implementation of waste management plans (WMP) and a recipe of solutions to these problems to facilitate its usage in Nigerian construction projects. It also to examine the importance of WMP, contents and procedures for its implementation from previous works in some countries. A research methodology, consisting of a literature review and a field study, was designed to achieve the research objectives. The literature review investigated the importance of WMP; its contents and procedures for appropriate implementation in San Mateo, Los Angeles, UK and Nigeria. The field survey involves the usage of a questionnaire administered to the targeted population involving private and public construction companies in Nigeria through convenience sampling technique. Data were retrieved and coded manually from the questionnaires after they were returned. These data were tabulated and frequency count was used to identify the rate of occurrence of the problems and the usage of the solutions suggested. As many as 18 respondents suggested 22 problems facing the implementation of WMP while 16 respondents proffered 22 solutions to these problems. Nine out of the 18 respondents who submitted the problems suggested cost/capital involved in executing WMP while ten out of the 16 respondents who proffered solutions posit education/training/ enlightenment of staff on WMP as solution. It is also discovered that various governments in the world are recognizing the importance of and the need for WMP on construction projects. The study therefore recommends inter-alia that intensive awareness and training programmes for staff of construction companies be embarked on to combat these problems of implementation of WMP on construction projects in Nigeria as it is done in other countries investigated.
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    Open Access
    Investigating the application and impact of concrete admixtures in construction projects.
    (Australasian Universities Building Education Association (AUBEA), 2023) Oladiran O.J.; Komolafe T.A.; Okonkwo C.
    Admixtures are chemical substances used to alter the properties of concretes to desired outcomes. They are used in varying ways due to a number of factors. This study investigates the application and effects of admixtures in concrete on construction projects. The specific objectives include to find out the commonly applied concrete admixtures in construction projects; to examine the extent of usage of admixtures in construction projects; to determine impact of admixtures on concretes; and assess the outcome of concretes from various admixtures in construction projects. Questionnaires were used to elicit information from construction professionals in Lagos State, Nigeria. Purposive sampling technique was used to select a sample of 120 respondents. Data were analysed using descriptive statistical tools such as frequency, percentage, mean score and ranking. The study revealed that retarders and super plasticizers are the commonest used admixtures in concrete; while strength improvement is what admixtures impact most in concretes. It is concluded that while admixtures alter properties of concrete, their usage are determined by the desired concrete outcomes. It is recommended that concrete producers should be cognizant of the various available admixtures for specific purposes. This can be done by familiarizing themselves with the manufacturers’ instruction of the various admixtures. Requisite practitioners should also specify the type and quantity of admixtures to be used in concretes to forestall wrong application. This can be achieved by ensuring that specifiers are proficient in the application of the admixtures specified.
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    Open Access
    Lean-in-Nigerian construction: state, barriers, strategies and “go-to-gemba” approach.
    (IGLC-16, 2008) Oladiran O.J.
    Lean-in-Construction, which is alien to Nigerian construction process, offers valuable techniques to manage construction at improved workflows and minimal waste generation. This paper therefore examines the exportation of lean to the Nigerian construction process by exploring the practitioners’ extent of knowledge and scope of application of lean techniques. However, the survey research involving ten companies via quota sampling technique and personal interviews is based on Toyota production principles only i.e. lean production. The paper reveals key strategies for absorption of lean with approaches to build and improve on JIT and concurrent design and construction in Nigeria. It therefore recommends these suggested-strategies for the entrenchment of lean in Nigerian construction process to combat waste generations and enhance workflows.