PROFESSIONALS’ PERCEPTION OF MAIN CAUSES ON MATERIALS WASTES IN NIGERIA BUILDING CONSTRUCTION INDUSTRY

1. Department of Architecture, Faculty of Environmental Studies, Olabisi Onabanjo University, Ago-Iwoye, Ogun State, Nigeria. 2. Department of Architecture, College of Science and Technology, Covenant University, Ota, Ogun State, Nigeria. 3. Ph.D Student, Department of Architecture, College of Science and Technology, Covenant University, Ota, Ogun State, Nigeria. ...................................................................................................................... Manuscript Info Abstract ......................... ........................................................................ Manuscript History Received: 16 February 2020 Final Accepted: 18 March 2020 Published: April 2020


ISSN: 2320-5407
Int. J. Adv. Res. 8(04), 856-861 857 (khyomesh and chetna 2011). The scope of materials waste is vast, and this waste occurs in the industry irrespective of the size of the building firm, instructions about handling, storage and stacking are not provided with the goods or sent in advance to the site (Abdulazeez, 2000).
Ensuring the timely flow of materials is an important concern of material management (Shah, 1993). Thus, Materials management is an important element in project management. If materials are purchased too early, capital may be held up and interest charges incurred on the excess inventory of materials (Wendy, 2006). Due to the high cost of materials, if not properly managed during the period of execution of the contract can lead to the abandonment of the project. Therefore, attention must be paid to how materials are been procured, stored and managed in order to achieve perfect work, effective handling of materials, right usage of materials and control of construction resources.
This, explain the reason why Johnston (2001), noted that Materials management begins with planning and estimation, these can be achieved through proper site co-ordination measure of reducing wastes, the location and security of materials on sites, procurement of quality materials as being specified and effective administration of site together with quality control. Lee and Donald (2001), observed that the problem associated with the absence of proper materials management on construction site could be wastage of resources making contract cost more than the budget sum, reduction of the profit margin of the contractor ineffectiveness of project handlings reduction of output etc.
According to Ademeso and Windapo (2008), poor planning and control of materials, lack of materials when needed, poor identification of materials, re-handling and inadequate storage cause losses in labour productivity and overall delays that can indirectly increase total project costs. Materials management functions include planning and taking off materials, vendor evaluation and selection, purchasing, expenditure, shipping, material receiving, warehousing and inventory, and material distribution. Materials management can only produce what it should with the right quantities of the right material at the right time (Arnold and Chapman 2004).
The present state of the building construction industry in Nigeria reflects various problems ranging from delays in project execution/delivery, substandard work, disputes, to cost and time overrun as a result of material shortage and wastages on sites, theft and displacement of materials on sites, as well as poor accounting and security system of the concerned sites/firms (Adafin, 2011). Non-compliance strictly with project bill of quantities, schedule of materials, specifications and construction programme in material stock control practice is another contributing factor which tends gradually to decrease the profitability of a project also often leads to the extension of time respectively, and hence no proper material stock control practice (Inyang Udoh, 2002).

Research Method:-
The primary data was attained through field survey. In order to collect data and to meet the setobjectives of the research, a structured questionnaire based on the aim of this study was designed. 261 questionnaires were randomly administered among the built environment professionals (Architects, Builders, Engineers, Quantity Surveyor, Town Planners, and Project Manager etc.) across the six (6) states in south-west Nigeria at a senior cadre level in all categories of construction firms duly registered with the corporate affairs commission in Nigeria, descriptive statistics were adopted for the analysis of the data.

Discussion of Findings:-
The data collected for the purpose of this study were evenly supplied by professional in all various types of construction firms where materials managements are being administered. Demographics show that shows that 14.2% of the respondents are (National Diploma Certificate) ND holders, 24.5% are (higher national diploma) HND holders (3.1). In summary, about 75.3% of the respondents have first, second degree and above. The distribution of respondent's profession is shown in table 3.1, show that the highest concentration of the respondents wasthe project manager (27.6%), next are builders (33.9%), then Engineers (16.9%), Architect (22.6%) Quantity Surveyor (7.3%), while 2.3% are for remaining professions. The study confirmed that 46%% of the respondents have been working with construction firms for more than sixteen years while about 19.5% have experienced between 11-15, and 34% had working experience ranges from ten (10) years and below.

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The result of analysis of professional perception on material management practices revealed that the person incharge-of managing construction material is the store manager (53.3%), followed by the project manager (10%), then General Manager (10.3%) while site engineer (16.9%) and others (9.6%). However, the result of the finding of professional responsibility for the ordering of materials confirmed that (72.8%) of the respondents for procurement department responsible for ordering materials, (8%) of the project manager responsible for this duty, (10.7%) for site engineer while (4.6%) of the General Manager for the ordering of materials and (3.8%) for others. The result of analysis on the component of materials management in table 3.2 shows that material estimation, budgeting, planning & Programming has mean value (4.9) follow by Waste management (4.8), followed by scheduling, purchasing and procurement and Inventory control, storage and warehousing (4.6), material handling and transport (4.4) while Receiving and inspection (4.2). the result of causes of materials waste on sits in table 3.3 established that, (4.8) respondents strongly agree that handling of materials is the major cause of materials wastage, follow by lack of site materials control, workers mistakes, and design changes and revisions causes a waste increase (4.7) while (4.6) of the means value believes that Lack of waste management plan, Over-ordering or under-ordering due to mistakes in quantity surveys and Ordering of materials that do not fulfil project requirements defined on design document causes a waste increase on construction site.