A STUDY OF CONSTRUCTION MATERIAL WASTE MANAGEMENT .

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A STUDY OF CONSTRUCTION MATERIAL WASTEMANAGEMENT PRACTICES BY CONSTRUCTIONFIRMS IN NIGERIAA. A. Dania, J. O. Kehinde and K. BalaDepartment of Building, Ahmadu Bello University, Zaria, Kaduna State, 800001 NigeriaEmail: [email protected]: Construction Waste Management is an aspect of Sustainable Development,which is fuelled by the growing concern for the effect of man’s activities on theenvironment. The management of Construction processes to reduce, reuse, recycleand effectively dispose of wastes has a serious bearing on the final cost, quality, timeand impact of the project on the environment. This research studied the practice ofConstruction Material Waste Management by firms in Nigeria by the use of structuredquestionnaires to senior construction-professional personnel of construction firms.The study found out that specific Government legislation on wastes from constructionsites were non-existent and that the respondents considered other project goals oftimely project delivery, quality and cost as more important than the impact of theproject on the environment. Most respondents displayed a poor understanding ofwaste management and most companies did not have a policy on Material WasteManagement. The paper recommends that the Nigerian Government puts in placelegislation regarding construction site waste management. Professional bodies andacademic institutions in the country should seek to further educate their members onthe importance of effective material waste management strategies.Keywords: Construction Waste Management, Government Legislation, Nigeria,Policy, Sustainable Development.1. INTRODUCTIONThe building or construction industry involves different processes and utilizes hugequantities of resources. These processes have severe impacts on the environmentwhich according to Horsley (2003), occur over a variety of timescales from theextraction and processing of raw materials used in construction, through the durationof the construction process, the operation of the building, up to the eventualdemolition of the structure at the end of its operative life.Construction activities have been known to generate large and diverse quantities ofwaste. According to the US Green Building Council, (2001), it accounts for up to 30%of total waste output in the United States alone, put at about 136 million tons perannum. As a result, construction and demolition waste management has become oneof the major environmental problems in many municipalities (Faniran and Caban,1988; Kibert, 1994; Ferguson et al., 1995; Graham and Smithers, 1996; Guthrie et al.,1999; Symonds, 1999; Lawson and Douglas, 2001, cited in Poon et al, 2004).In some more advanced countries, the concern for the effect of Man’s endeavours onthe environment and rising project costs has increased the drive for the application ofConstruction Waste Management. There has been a strong drive to ‘do more with less’by reducing waste at all stages of construction as identified by the ‘Rethinking121

Construction’ task force in the UK (DETR, 2000). There is also a need to improvematerial handling by contractors as the DETR also noted that about 13 million tonnesof the estimated 70 million tonnes of construction and demolition materials compriseof materials delivered to site and thrown away unused.1.1The Effect of Construction ActivitiesConstruction can be defined as the activity involving creation of physicalinfrastructure, superstructure, housing and other related facilities (Watuka andAligula, 2003). The physical substance of a structure is an assembly of materials fromwidely scattered sources. They undergo different kinds and degrees of processing inlarge numbers of places, require many types of handling over periods that vary greatlyin length, and use the services of a multitude of people organized into many differentsorts of business entity.The Construction industry, while contributing to overall socio-economic developmentof any country, is a major exploiter of natural non-renewable resources and a polluterof the environment whereby it contributes to the environmental degradation throughresource depletion, energy consumption air pollution and generation of waste in theacquisition of raw materials (Watuka and Aligula, 2003).Construction activities generate a large amount of waste compared to other industries.In EC countries, about 200 to 300 million tons of construction and demolition waste isproduced annually, which translates to roughly a 400 km2 area covered withdemolition debris one meter high (Pieterson and Fraay, 1998, cited in Elias-Ozkan andDuzgunes, 2002). In the United States alone, about 136 million tonnes of constructionwaste is generated (US Green Building Council, 2001).1.2Sustainable ConstructionAccording to Harman and Benjamin, (2004) the built environment is the heart of anyeconomy; providing the infrastructure necessary to enhance productivity, but themanner in which it consumes natural resources makes it responsible for some of themost serious local and global environmental changes. Sustainable construction is anintegrative and holistic process of construction which aims to restore harmonybetween the natural and the built environment (Agenda 21, 2001).The California Integrated Waste Management Board (2003) described SustainableConstruction as a whole building approach to design and construction that saves orreduces resources in five categories: site, water, energy, materials and environmentalquality. Sustainable construction, according to Watuka and Aligula (2003) can also besaid to be “the set of processes by which a profitable and competitive industry deliversbuilt assets: building structures, supporting infrastructure and their immediatesurroundings which:i.ii.iii.iv.Enhance the quality of life and offer customer satisfactionOffer flexibility and the potential to cater of user changes in the futureProvide and support desirable natural and social environmentsMaximize the efficient use of resources while minimizing wastage.”122

1.3Material Waste in ConstructionThere are differing views held by researchers as to what constitutes Constructionwaste. Cheung, (1993) stated that Construction Waste can be defined as the byproduct generated and removed from construction, renovation and demolitionworkplaces or sites of building and civil engineering structures. According toFormoso, (1999), it should be understood as any inefficiency that results in the use ofequipment, materials, labour, or capital in larger quantities than those considerednecessary in the production of a building. Shen et al,(2003) defined building materialwastages as the difference between the value of materials delivered and accepted onsite and those properly used as specified and accurately measured in the work, afterdeducting the cost savings of substituted materials transferred elsewhere, in whichunnecessary cost and time may be incurred by material wastages.Serpell et al, (1995), cited in Alwi et al, (2003) asserted that Construction Managershave to deal with many factors that may negatively affect the construction process,producing different types of wastes. There are several causes of material wastes whichin most cases are dependent on the type of construction methods employed, thespecific materials in use, and/or the stage of the construction itself. Waste can begenerated by mistakes, working out of sequence, redundant activity and movement,delayed or premature inputs and products or services that do not meet customer needs(Construction Industry Board, 1998).Construction and Demolition waste is a complex waste stream, made up of a widevariety of materials which are in the form of building debris, rubble, earth, concrete,steel, timber, and mixed site clearance materials, arising from various constructionactivities including land excavation or formation, civil and building construction, siteclearance, demolition activities, roadwork, and building renovation. It also includesincidences of wastages in labour and energy used in construction works. However,material waste has been recognized as a major problem in the construction industrythat has important implications both for the efficiency of the industry and for theenvironmental impact of construction projects (Formoso et al, 2002). Mostconstruction wastes which were previously regarded as inert have been found togenerate harmful leachates which have negative effects on the environment(Apotheker, 1992, cited in Lingard et al, 2000). As such, it is absolutely imperative forthe construction industry to adopt ecologically sound planning and constructionpractices for the purpose of creating a healthy and sustainable built environment (Poonet al, 2004).1.4Construction Waste ManagementThe practice of waste management for construction activities has been promoted withthe aim of protecting the environment and the recognition that wastes fromconstruction and demolition works contribute significantly to the pollutedenvironment (Shen et al, 2002, cited in Shen et al, 2004). This increasing awareness ofenvironmental impacts from construction wastes has led to the development of wastemanagement as an important function of construction project management (Shen et al2004).123

There are several approaches to construction waste management. The process ofmanaging construction waste goes far beyond the disposal of the wastes itself. It is anall-encompassing strategy to effectively utilize construction resources, with the viewto reducing the quantity of waste and also utilizing the generated waste in the mosteffective manner. The most common approach to management of construction wasteis dumping in landfill sites. However, decreasing landfill space has led to increasingcosts of landfill disposal to the contractor (BIE, 1993, cited in Lingard et al, 2000).Also, a relatively large amount of materials is being wasted because of poor materialcontrol on building sites (Poon, et al, 2004). This has prompted the need foralternatives for waste prevention and the initiatives to reduce, reuse and or recyclewaste produced which are referred to as the three R’s of construction wastemanagement. A waste hierarchy has been widely adopted as a guide for constructionmanagers, in line with the principles of sustainable construction. The Waste hierarchysuggests that:i)ii)iii)iv)The most effective environmental solution may often be to reduce thegeneration of waste.Where further reduction is not practicable, products and materials can sometimesbe re-used, either for the same or a different purpose.Failing that, value should be recovered from waste, through recycling,composting or energy recovery from waste.Only if none of these solutions is appropriate should waste be disposed of, usingthe best practicable environmental option.(Source: Department of the Environment, Transport and Regions, 2000)According to Coventry and Guthrie, (1998), there are two fundamental reasons forreducing, reusing and recycling waste: the economic advantages, and theenvironmental advantages. The environmental advantages include the minimization ofthe risk of immediate and future environmental pollution and harm to human healthwhile the economic advantages include lower project costs, increased businesspatronage, lower risk of litigation regarding wastes amongst others. In view of theseadvantages and the negative impact of construction wastes on successful projectdelivery, this paper identifies major causes of waste, the position of construction firmsand professionals in the Nigerian construction industry on construction wastemanagement and constraints to effective site waste management such as policy andlegislative issues.2. METHODOLOGYThe research work was carried out by administering a well structured questionnaire toa sample of the population for the study. The population was all professionals in theconstruction industry, i.e. Architects, Builders, Engineers and Quantity Surveyors whowere managing construction projects at a senior cadre level in all categories ofconstruction firms duly registered with the corporate affairs commission in Nigeria.Twenty-Seven (27) of the returned questionnaires were administered at a conferenceon Sustainable Construction, while the other Thirty-Five (35) were administered toprofessionals handling projects in large cities like Kaduna, Lagos and Abuja.124

The questionnaire was designed in such a manner to elicit responses that could beeasily analysed by the use of closed ended questions with suggested answers onordinal scales. In addition, the opinions of the respondents were also sought withrelevant open ended questions a view to finding suitable recommendations on thefindings of the research. The questionnaire was used to gather information on therespondents’ knowledge of Construction Waste Management, legislation and therespondents’ company’s policy of waste management.3. FINDINGS AND DISCUSSIONA total of 120 questionnaires were administered for this survey, of which 62 werereturned with valid responses. This showed a response rate of 51.6%. From the resultsof the analysis, it was observed that about 12.9% of the respondents were of theopinion that no attention at all was paid to construction waste management. About77.4% felt it was fairly given as much attention as other functions of a constructionmanager, while only 9.7% opined that sufficient attention was paid to constructionwaste management.The research also showed that a fairly high percentage of the respondents were able toidentify the most appropriate description of construction waste management from alist of options. From column 3 in Table 1, it can be seen that 52.5% chose option 4which encompassed about all aspects of construction waste management. All otheroptions contained only some aspects of waste management. On the level of wastesencountered on site, 61.3% of the respondents regarded the level of waste generatedon their sites as Moderate. Approximately twenty three percent felt it was low while12.9% regarded it as high. The summary of these responses are presented into Table 1.Table 1: Awareness on Construction Waste Management IssuesUnderstandingOption12345Waste Level%0.014.826.252.56.6RankWaste ManagementAttention%Very LowLowModerateHighVery 77.412.9Legend: 1 Supervising workers thoroughly to reduce waste, 2 Proper material scheduling and handling toreduce waste, 3 Proper disposal of wastes in landfills and suitable areas, 4 Efficient material handling andreduction, reuse, recycling and disposal of wastes, 5 Reduction and disposal of construction wastesFurther analysis showed that the project goals of cost and quality were considered bythe respondents as most important; more important than timely delivery of the projector minimizing the impact of construction on the environment as shown in Table 2.Table 2: Level of Importance of Project Goals to Construction ProfessionalsFactor1(%)2(%)3(%)4(%)MeanStd. 813.810.400.40125

TimeImpact .490.79Legend: 1 Indifferent, 2 Not Important, 3 Important, 4 Very ImportantMany of the respondents showed a poor adoption of different methods of managingconstruction wastes. The most widely adopted methods were reusing and sale as scrap,largely due to the high use of timber in construction and its high scrap value for usessuch as firewood. This was buttressed by the observation that only 42.6% weresatisfied with the methods of waste management on their sites. Roughly 20% wereneutral while 32.8% expressed that they were dissatisfied with their methods.The low level of adoption may be explained by the fact that respondents showed apoor understanding of the benefits of an effective construction waste managementscheme. Majority felt lower project costs (69.4%) and cleaner environment (66.1%)were the principal benefits of construction waste management as shown in the tablebelow. Other factors such as increased business patronage and longer lifespan of nonrenewable sources of materials were not widely thought to be important (See Table 3below).Table 3: Benefits of Construction Waste ower ProjectCostsLonger Lifespan 3.296.811.388.712.987.1Of the respondents who practised some form of waste management, 56.7% cited thereduction of the project cost reduction as the main motivation, followed by concernfor the environment of which 43.3% attested to. Thirty percent cited conditions ofcontract, while other factors such as legislation, client requirement and governmentincentives had only 13.3%, 6.5% and 0% respectively. Table 4 below shows thepercentages and rankings of the various factors, while Table 5 shows the percentagesand ranking of some factors that hinder the practice of waste management on site.Table 4: Factors Influencing the Practice of Construction Waste ManagementFactorProject procurement cost reductionConcern for the environmentConditions of ContractsLegislationClient RequirementGovernment incentivesAgree (%)Neutral 00.0123456126

Table 5: Factors Hindering the Practice of Construction Waste ManagementFactorAgree (%)Neutral (%)RankLack of awareness46.753.31Weakness in legislation23.376.72Insignificant cost of handling waste20.080.03Waste not a problem on site13.386.74Other factors10.090.05Abundance of landfill6.793.36The general observation from the results of the analysis was that the practice of wastemanagement by construction firms in Nigeria is poor. Seventy-two percent claimedthey were not aware of any legislation on construction wastes, and only 48.4% saidthey worked in companies with policies on construction waste management. Seventytwo percent claimed to be in a position to influence policy making in theirorganisations but only 45.8% of them attested to have formulated one (See Table 6).Table 6: Policy and Legislation Issues on Waste ManagementResponseWasteLegislation(No 58)%YesNo27.672.4Company WasteManagement Policy(No 62)Influence onPolicy(No 62)Formulation ofPolicy(No 48)72.627.445.854.2%%48.451.6%With respect to the causes of waste on site, several factors were obtained from thework of Tam et al, (2003) and the respondents were requested to rank from 1 throughto 5 (i.e. from strongly disagree to strongly agree as shown in the legend below theTable). The means for each of the factors were computed and used to rank the factorswith respect to their significant contribution to waste generation. From the resultswhich are shown in Table 7 below, Poor supervision, workmanship and storagefacilities were regarded as the most common causes of waste on site, while equipmentmalfunction, weather and force major were the least common.Table 7: Causes of Waste on Construction SitesFactorsPoor SupervisionPoor WorkmanshipPoor Storage FacilitiesImproper HandlingImproper StorageDesign ErrorDesign ChangesHuman ErrorMaterial DeteriorationNo Waste .181.24Rank12345678910

PersonnelOrdering ErrorsForce MajeureWeatherEquipment 01.081.2511121314Legend: 1 Strongly Disagree, 2 Disagree, 3 Neutral, 4 Agree, 5 Strongly AgreeThe research also attempted to find out factors which may impact on the effectivenessof a solid construction waste management scheme and as such, several factors adoptedfrom the work of Lingard et al, (2000), were included in the questionnaire and theywere ranked according to their perceived impact on waste management by therespondents. Table 8 shows the distribution of the responses, the means, standarddeviation and rank (based on mean) for each factor.Table 8: Factors Which May Affect the E

Construction Material Waste Management by firms in Nigeria by the use of structured questionnaires to senior construction-professional personnel of construction firms. The study found out that specific Government legislation on wastes from construction sites were non-existent and that the respondents considered other project goals of