An Overview Of A Constructions Productivity Construction Essay

An Overview Of A complex body parts productivity turn EssayRecently, whirl productiveness is on a long- status slide and it is recognized as perseverance ch solelyenge. System, people, materials, in excogitateation and energy must flow forceively and efficiently to maturate its objective at high productiveness to gross(a) build at lowest possible be with possible shortest periodframe (Picard, 2005).Productivity is critic completelyy meaning(a) in facial expression industry. more a nonher(prenominal) researchers do believe uttered their concern in all over productiveness in look industry. Defining productiveness is not a simple task to everybody. Different people will ease off various definition and understanding. Most of them agreed that marketable issue was essentially the consequential measure apply.Increased productiveness was a leading concern to all Committee s absentholders much(prenominal) as users, contractors, and construction jade unions and led by the owner. The construction users emphasized the need of collecting data directly applicable to productiveness improvement. The Committee was concluded that the front-line construction foreman/supervisor would be a reliable source of information. These informants would be asked to offer up their judgment of the sterling(prenominal) impediments to a productive construction catch (Tucker, 2003).Definition of productiveness in spite of appearance these several(prenominal)(prenominal) decades, many researchers suck fastend the productiveness term in their studies in a number of ways. The term productiveness has polar meanings to different people. homophiley individuals automatically think only of jade unions when the term productivity is mentioned. Others associate capital expenditures with the term. Each of these interpretations is only partly correct (Adrian, 1993). Many researchers have attempted to define littlely the meaning of productivity and on a lower floor be some of it that referred from their studiesOglesby et al. (1989), presented that productivity discharge be defined as in-place value divide by enters . Some researchers have defined it as flows-hours divided by the equivalent quantity of break. In construction, productivity normally can be understood as work quantity divided by man-hours (or work-hours) consumed to accomplish the work.Productivity = Work QuantityMan-hours concord to Dolman, Parham, Zheng, (2007), productivity is a measure in order to know how much output is produced per unit of measurement of stimulus.Diewert Lawrence, (2006) presented that productivity can be defined as the aim of scotch output per unit of input and withal per thespian. Productivity is important to the wealth and well-being of a nation and give efforts to improve productivity occur at all aims of society. match to Hwang and Liu, (2005), productivity is an effective power that can indicate output of construction work quanti ty versus the input of resources. Productivity of a crew is directly forces the cost and date postulate to complete a task. By analyzing and forecasting productivity, fancy addressr can be more effective to retain and predict toil time and cost doneout execution up to completion.Thomas and Mathew, (1986) presented that no standardized productivity definition had been established in the construction industry. It is difficult to define a standard productivity measure because companies use their own forms which atomic number 18 not standardized. Association simply illust evaluate the productivity between an output and an input. The form has been widely used and existing in publications over the days in construction industry is Productivity = Input/OutputProkopenko, (1987), defined the productivity as effective and efficient utilization of all resources, proletariat, pose and materials. consort to Jugdev, et al.,(2001), productivity is a ratio between inputs and outputs. I n conniving the productivity, it is important to specify the inputs and outputs that to be thrifty because on that point argon many inputs such as labors, materials, equipments, tools, capital and externalize in construction system.Uusi-Rauva and Hannula, (1996), presented that productivity can be defined as internal efficiency of the constitution or other object to be measured. A more precise definition of productivity is the following output divide by the input that is used to generate output. Output is consists of products or function and input is consists of materials, labor, capital, energy, etc. Productivity is not only affected by the quantities of inputs and outputs but withal the qualities of inputs and outputs. fit to Halligan, et al., (1994), there are many ways to define productivity. In construction, it is usually taken to mean labor productivity which is units of work set or produced per man-hour.Teicholz, (2004), express that productivity in construction in dustry was measured by constant contract dollars of new construction work per periodical work hourThe Bureau of tire out Statistics (BLS, 2009) of the U.S. Department of Labor was defines productivity into two type which are labor productivity and multifactor productivity. Labor productivity can be measures as output per hour of labor and it is used in over 40 industries including construction. Productivity can be reckon by dividing the quantity of work completed (Quantity) by number of labor hours used to complete the work (Man Hours). A productivity value represents deed of an operation with respect to time and cost, where activity duration and activity cost is directly affected by productivity.Duration (Hours) = Quantity of Works(Quantity / Man Hours)= Quantity of WorksProductivityThe formula above indicates how critical the dependableness of the productivity factors in estimation time.Measurement of productivityThere is lean surrounding productivity that rooted in the diff erences in data collection. It is referable to incorrect in assuming productivity measured uniformly and that all published productivity values have the same basis (Whiteside, 2006) overall conception of productivity is difficult to express or to measure. It is sometimes expressed either in terms of output from labor or from services or from capital invested. These split of expressions oftentimes do not give an accurate picture of the overall position. Although, there are measurements of some or all of the inputs and outputs of the industry but they still failed to combine these measurements into any fine measure of efficiency. In fact, the ratio is easy to compute if the unit uses a single input to produce a single output (Choy, 2008).According to Whiteside, (2006), production is average direct labor hours to install a unit material. He besides tenseed that in perfect world, perfect productivity (1.0) will be accomplished in 40-hour work week, with everyone taking all of the ir holidays and vacation days planned. It is regarding to all the unionizeing drawings must be coulomb% complete, there would be no delays of any kind, everyone would work safely, everything would fit abruptly at the first time, the weather would be 70 degrees Fahrenheit and there would be no litigation at the end of the throw off. But, we do not live in perfect world and true productivity is often poorly understood. The first challenge in understanding productivity is abstracted of common terms. The definition of hours identified as direct labor should be consistent. Second is too much focus in determining productivity which is incorrectly placed on the individual worker. Productivity is something to do with the worker because many workers work at the same rates. The primary(prenominal) thing should be focused in productivity measurement is proper or complete planning. It is because like-out-sequence work will contribute to lower productivity due to the refashion hours requir ed to complete the original task. The final challenge is how to make productivity comparison when the data used in productivity studies before have the same basis. Productivity is not based on profits rates or cost data alone and it is improper to combine wage rate, hours and material quantities to make productivity comparison.According to Hwang and Liu, (2009), construction productivity studies have centered on the identification of factors that influence productivity and quantification of the impact of such factor on productivity. As a result, there were various soft and quantitative factors have been discovered and various methods for productivity have been presented. volume of those methods are based on relationships between productivity and factors. Based on Thomas and Yiakoumis (1987), they stated that theory underlying the factor lay is the work of crew is affected by a number of factors. If the cumulative effect of these disturbances can be mathematically represented, a nd then the expected substantial productivity can be estimate. But, it is not always feasible to quantify the impact of various factors and represent the relationships mathematically. Another limitation is the value of many associate factors in future is not available and thus, they have to be estimated. In fact, some of the factors can be correlated with others which the correlation whitethorn be higher or lower under different situations.There is several research efforts have been devoted to developing models. The models that being used in the construction industry are such as belowAccording to Sonmez and Rowings, (1998) Portas and AbouRizk, (1997), recommended Neutral Network (NN) techniques which have been used to develop method of productivity prediction.Everett and Farghal, (1994), recommended learning curves that for various activities.Abdelhamid and Everett, (1999), have applied time series compend to evaluate hoisting performance comparing the CRANIUM technology with the conventional technique.According to Brockwell and Davis, (2002), ARMA (autoregressive moving average) models are used to model time-lagged relationship of self-correlated observations within a single series.Cumulative Average and Simple Moving Average that sagely used to model a single time series exponential Smoothing produce forecasts of saddleed value of past observation with exponentially decrease weights (NIST, 2006).Although there are numbers of publications exist on construction productivity, there is no agreed upon definition of work activities nor a standard productivity measurement system. Most of researchers have concluded that it is difficult to obtain a standard method to measure construction labor productivity because of externalize complexity and unique peculiar(prenominal)s of the construction confuses (Oglesby et al. 1989). The uniqueness and non instant of operation in construction projects make it is difficult to develop a standard productivity definition a nd measure (Sweis, 2000).Current measurement of productivity in construction industryOur labor productivity experts specialize in labor productivity analysis and may utilize the following industry-recognized methodologies, where appropriateMeasured cubic centimetre AnalysisWork SamplingComparable Work Study commonplace and Specialty intentness Studies (Mechanical Contractors Association of America MCAA,Construction Industry instal CII, Business Roundtable, etc.)Total appeal MethodModified Total Cost MethodTime and Motion StudiesThe selection of a particular productivity analysis methodology is depends on the project facts, the temper of the events being analyzed, the nature and extent of available labor data and may vary from project to project. Each of the above-referenced productivity analysis methodologies has inherent its own advantages and disadvantages. Interface Consulting has extensive see to it handling construction labor productivity claims and construction claims c onsultants are skilled at tailoring productivity analysis approach to outfit a projects needs and const raints (ICII, 2009).Factors influence productivity in constructionAccording to Tucker, (2003), he presented the most factors that can affect the construction productivity peculiarly on situation as belowDesign special(prenominal)ations, drawings, documents have to be improvedField stand out for timely responses have architect/engineer on site with palm competencyCoordinate Design/ retreadTimely RFIs/RFPs (Request For Informations/Request For Proposals)Construction/ look wariness competencyHe also suggested that productivity improvement should be done based on this areaConstructability of the design documents with input of major contractors on account quality and realismCoordination among major contractorsPre-project planningCommunication and teamwork between owners, design professionals, contractors and laborImprovement of the construction management process.Parisi, (2008 ) presented that potential factors influence the construction productivity are many, including out-of-sequence work skilled labor shortages worker crowding/ clog up work areas interference of trades owner interference design problems and defects contractors inadequate management/supervision failure to properly staff the project overtime and acceleration.Lim et al (1995) studied factors affecting productivity in the construction industry in Singapore. Their findings indicated that the most important problems affectingproductivity were hindrance with recruitment of supervisors difficulty with recruitment of workers high rate of labour turnover absenteeism from the work site and communication problems with foreign workers. Olomolaiye et al (1996) studied factors affecting productivity of craftsmen in Indonesia, with their findings indicatingcraftsmen in Indonesia spent 75 % of their time working productively. Five specific productivity problems were identified ie lack of materials rew ork absenteeism lack of equipment and tools.Kane et al (cited in Herbsman et al, 1990) classified factors affecting construction productivity into two principal(prenominal) roots technological factors and administrative factors.The technological factors encompass those related mostly to the design of the project the administrative group factors relate to the management and construction of the project. proficient factors comprise sub-groups such as design factors, material factors and location factors. administrative factors comprise sub-groups, such as construction methods and procedural factors, equipment factors, labour factors, and complaisant factors. Heizer and Render (1990) classified factors influencing site productivity into 3 groups labour characteristic factors project work conditions factors and nonproductive activities. Olomolaiye et al (1998) stated that factors affecting construction productivity are rarely constant, and may vary from country to country, from proje ct to project, and even within the same project, depending on circumstances. They classified factors influencing construction productivity into 2 categories external and internal, representing those outside the control of the firms management, and those originating within the firm.. External factors include the nature of the industry, construction client knowledge of construction procedure, weather, and level of economic development. Internal factors included management, technology, labour, and labour unions. Enshassi et al 2006, Enshassi et al 2007, and Al Haddad 2007 stated that among the problems which the Palestinian construction industry is facing are material furnish schedules and project computer programing techniques. Although a number of cooking courses were conducted to local contractors, these training efforts did not focus enough on the abilities to use project programing techniques such as Microsoft project and Primavera. Therefore training effort should also be tai lored to improve methods of recording productivity and ways of productivity improvement on construction sites.The important productivity rate in project schedulingThe duration of construction project is a primal factor to consider before starting a new project which is it can be determine project success of failure. Despite the precariousness and risk level is very high in construction industry, original construction planning which is more relies on traditional deterministic scheduling method is still not clearly ascertain the level of misgiving snarled in the project. Subsequently, it can prolong a projects duration and cannot be completed within the allocation time of the project (Lee, et al., 2009).Construction projects are subjected to changes which it require constant performance monitoring and follow-up schedule updates. Project manager must take proactive attitude to analyze project data and to predict potential problems and delay in order to make timely decisions and t o reduce the negative impact on cost and schedule (Hwang and Liu, 2005).Planning in construction is a complex and iterative process. A plan usually is prepared based on the estimates by the participants actual commitment. Therefore, construction productivity plan plays a significant role in the process. Based on Parisi, (2008), in estimating labor, there are several distinguish factors that should be consideredProductivity of its field forcesUnion labor agreements and requirementsPast experience with the owner, designer, and construction managerLabor availabilitySpecialty tradesTherefore, if the actual construction work deviates from the anticipated plan, once the contract is signed and the project is underway, several situations may result as belowThe job may take more time because the progress is not being made at the rate projected in the original baseline schedule and thus, project completion must be extended. (In such cases, acceleration of the remaining activities may be impl emented to recover time)More hours of labor may be required to install the work items because materials are not being installed by the contractors workforce at the productivity rates (the anticipated quantities of material to be installed per hour) same as estimated in the original bid.An overrun of both time and labor may occur.In order to succeed, the companies must make a phase affirmative action into the total management of productivity through a formalized, documented process such as depicted in Figure 2.0. The process should be started with historical productivity analysis. The knowledge that gained from this processes should then be utilized to forecast and manage future productivity. The supervisor that involved in this process must implement and monitor the predetermined productivity values. Only then the companies can be more competitive and in(predicate) in todays global marketFigure 2.0 A model to manage construction productivityConstruction industry seemed as low sect or when there is low technology and low skilled employments occur. According to Saad, (2002), in order to raise level of construction productivity, it is recommended that the projects should have the following features high gear degree of standardizationDesign is preferred to use pre-fabricated units or pre-assemble forming systemBuilding system should be easy and simple to construct and repetitiveWell managed construction methods with details planning and specificationHigh level of mechanized methods and skilled workersRoof worksRoof is a elemental human need is for shelter, which for most of us consists of a few walls and a crown over our heads. Roofs come in many shapes and sizes. One of the main reasons for having a detonating device is to keep out rainwater and snow. The selection of cap is based on the following characteristicsStabilityProtection from the sun, weather, wind and rainDurablityHeat resistanceBrightness and ventilationBeautyConstruction of chapiter must be str ong and able to support the load and stressed that going to happen. The load that is attributable to roof, firstly is dead load which is the weight of the roof trusses, roof covering secondly is live load which is consists of tools, equipment, workers, rain water and lastly is wind load. Wind is a major stress to the roof which is difficult to forecast accurately.Roof stability is depends on the support such as roof trusses, column, walls, beams and foundation of the building.Design of roof also takes into account the respective functions of the building. Building for residential and office should have a comfortable situation in terms of condition, light, air and dam parts great(p)s. Industrial buildings and warehouses may require heat insulation on the roof to maintain the same conditioning in buildings. Traffic in the building to allow use of the pillars supporting the roof of the short-range distance. Roof for battlefield and stadium, must be supported by long span of roof trus ses and the support in the middle will distrupt the view and noise and sound effect protection from the audience.Productivity work to be consider in roof worksThe productivity works to be considered in this study as below episode of roof trusses (cold form)Installation of insulationInstallation of roof covering (concrete roof tiles and metal decking)No. of workers in groupDaily Productivity (m2)METHODPRODUCTIVITY OF ONE WORKING dayHandlingHalf MechanizedFull MechanizedSummaryFrom the literature review of the productivity in construction is important especially to provide accurate duration of task in building project scheduling.RerefencesDolman, B., Parham, D., Zheng, S. (2007), thunder mug Australia match US productivity performance?, Retrieved whitethorn 7, 2007, from http//www.pc.gov.au/commission/work/productivity/publications/reports.html.Diewert, W. E. and Lawrence, D. (2006), Measuring the contributions of productivity and terms of trade to Australias economic welfare, Retri eved May 7, 2007, from http//www.pc.gov.au/commission/work/productivity/publications/reports.html.Oglesby, C.H., Parker, H.W. and Howell, G.A., (1989), Construction productivity improvements, McGraw Hill, New YorkAdrian, J.J. (1993), Construction Estimating An accounting and productivity approach 4th Edition, 1993Hwang, S. and Liu, L.Y. (2005), Proactive project control using productivity data and time series analysis, Computing in Civil Engineering 2005Thomas, H.R. and Mathew, C.T., (1986), An analysis of the methods for measuring construction productivity, SD 13, Construction Industry Institute, The University of Texas.Whiteside, J.D., (2006), Construction Productivity, AACE outside(a) Transaction, 2006Picard, (2005), Construction productivity qualifications, Cincinnati, Ohio, USAProkopenko, J.,(1987), Productivity management, geneva global Labor Office.Jugdev, K., Thomas, J. and Delisle, C., (2001), Rethinking project management old truths and new insight, International Proje ct Management ledger, 7(1), pp. 36-43Uusi-Rauva, E. and Hannula, M., (1996), Measurement A tool for productivity Improvement, 9th International Working Seminar on Production Economics, Innsbruck, pp. 13-29Halligan, D.W., Demsetz, L.A., Brown, J.D. and Pace, C.B., (1994), Action-response model and loss of productivity in construction, Journal of Construction Engineering and Management, Vol. 120 No. 1, March 1994Teicholz, P., (2004), Labor productivity declines in the construction industry Causes and remedies, AECbytes Viewpoint 4, April 14 2004.Tucker, W.W., (2003), Construction Productivity Study Summary, Eastern Michigan University, 2003.Choy, C.F., (2008), Productive efficiency of Malaysian construction sector, Built-Environment Department, Faculty of Engineering and Science, University Tunku Abdul Rahman, Malaysia.Lee, H.S., Shin, J.W., Park, M. and Ryu, H.G, (2009), Probabilistic duration estimation model for high-rise structural work, Journal of Construction Engineering and M anagement, December, 2009Hwang, S. and Liu, L.Y. (2009), Predicting short term productivity I Contemporaneous time series and forecasting Methodologies, Journal of Construction Engineering and Management, December, 2009Sonmez, R. and Rowing, J.E., (1998), Construction labor productivity modeling with apathetic network, Journal of Construction Engineering and Management, December, 124(6), 498-504Portas, J. and AbouRizk, S. (1997), Neutral network model estimating construction productivity, Journal of Construction Engineering and Management, 123(4), 399-410Everett, J.G. and Fargahl, S. (1994), Learning curve predictors for construction field operations, Journal of Construction Engineering and Management, 120(3), 603-614Abdelhamid, T.S. and Everett, J.G., (1999), Time series analysis for construction productivity experiments, Journal of Construction Engineering and Management, 125(2), 87-95NIST, (2006), Engineer statistic handbookOglesby, C.H., Parker, H.W., and Howell, G.A., (1989), Productivity improvement in construction, McGraw-Hill, New York.Sweis, G.J., (2000), Impact of conversion technology on productivity in masonry construction, PhD dissertation, Northwestern University, Evanston, III.Interface Consulting International, Inc.(ICII), 2009Parisi, R.F., (2008), When the best-laid plans go astray A primer on labor productivity, Capital Project Management, Inc.Saad, D.A, (2002), Standard labor productivity of reinforced concrete building structures and factor affecting on it, Thesis presented to university of Technology, IraqFACTORS AFFECTING LABOUR PRODUCTIVITY IN BUILDINGPROJECTS IN THE GAZA STRIPAdnan Enshassi1, Sherif Mohamed2, Ziad Abu Mustafa1 and Peter Eduard Mayer3