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The building construction industry significantly contributes to the economy, particularly in Tanzania, where the performance of building craftsmen is crucial to project success. This research identifies key factors impacting craftsmen's performance, including material shortages, management issues, and safety concerns. Recommendations for improving performance include ensuring material availability, enhancing supervision, and promoting motivation among craftsmen.
Journal of Civil …, 2007
Poor productivity of construction workers is one of the causes of cost and time overruns in construction projects. The productivity of labour is particularly important especially in developing countries, where most of the building construction work is still on manual basis. This paper reports on a survey made on project managers of building projects in Uganda, where an increase in productivity is being sought. Respondents were required to rate using their experience how 36 factors affect productivity with respect to time, cost and quality. The survey was carried out by a questionnaire and responses received over a period of 3 months. The ten most significant problems affecting labour productivity were identified as incompetent supervisors; lack of skills from the workers; rework; lack of tools/equipment; poor construction methods; poor communication; inaccurate drawings; stoppages because of work being rejected by consultants; political insecurity; tools/equipment breakdown; and harsh weather conditions. Although lack of materials is ranked highest with regard to average rating on loss of time, it was not ranked among the top ten using the importance index that takes into account time, cost as well as work quality. The policy makers and researchers should focus on the identified major factors in order to improve productivity.
PARIPEX - India Journal of Research, 2019
The construction industry is complex in nature, as it contains a number of project team members like the client, consultants, contractors, stakeholders, shareholders, and regulators who are responsible in overseeing the performance and time schedule of any building project. The study objective on factors affecting performance and time schedule for Multi-Unit Residential Buildings, (MURBs) construction projects in DarEs -Salaam, Tanzania, was to explore factors affecting performance and time schedule for MURBs construction in DarEs -Salaam, Tanzania. To documents and analyze factors that drives positively and negatively, the performance and time schedules for MURBs construction projects respectively, as well as to comment on mitigation measures that can improve performance and time schedule of MURBs construction projects. This study was designed to obtain views from MURBs project stakeholders, regarding their perception on factors that affects MURBs projects. Purposive sampling was adopted using a sample of 50 MURBs stakeholders from NSSF, NHC TBA, PPF, WHC, etc. Data were collected through structured questionnaire and literature review, and analyzed using Microsoft Excel while using tables presentation. 50 questionnaires were distributed to Quantity Surveyor, Architects, and Engineers in which 46 were returned. The finding reveals that 12 factors affect performance and time schedule for MURBs construction projects in DarEs -Salaam, Tanzania positively and negatively, in terms of cost, time and quality. The result showed that late payment, under estimation, inadequate planning and communication, lack of competent project manager, scope change, design change, conformance to the specification were the most factors affecting MURBs performance. Furthermore, it was found that late completion and late payments influence cost overrun, which eventually raise disputes and claims and sometimes arbitration. Moreover, some mitigation measures like ensuring proper planning of work, clear information and communication channels, clear information and hiring skilled labor and committed leadership and management were found to be of great help in addressing MURBs construction performance if well implemented. The study recommends the management structure of MURBs construction project to resemble the one in Australia, hence helping the Tanzanian construction industry, specifically the MURBs stakeholders.
International Journal of Engineering and Management Research (IJEMR), 2020
When it comes to a firm's growth, profitability and profit maximization are sensitive matters that cannot be neglected, due to the fact that profit and profit maximization are the main aims for any building construction business. Thus, the study intended to explore the profit maximization opportunities available for small and medium size building contractors (SMSBCs) in DarEs -Salaam, Tanzania; by exploring the profit maximization strategies employed; examining the challenges faced by these contractors that affect realization of profit maximization; and proposing profit maximization measures, that can be employed by the SMSBCs in DarEs -Salaam, Tanzania. This designed survey study, employed the SMSBCs in DarEs -Salaam Tanzania, as a unit of analysis, which involved building contractors from Class IV, V, VI and VII, as study population and unit sample. Moreover, the descriptive design survey study involved probability sampling as a sampling technique. Literature review; open and closed ended questionnaires, were used in collecting primary and secondary qualitative and quantitative data. In collecting data, total of 94 questionnaires were distributed, whereby 78 (84.3%) were returned. Quantitative data were analyzed using Statistical Package for Social Sciences (SPSS), while qualitative data were analyzed thematically. Findings revealed charging for all amendments and change orders; dropping of low performers; minimization of waste on site; timely execution of works on site; proper tendering procedures; improving construction productivity; reliable chain of supplies; and requiring more site job experience, as the most important opportunities employed by SMSBCs. Furthermore, the critical challenges revealed were; non-payment of debts; taxes and license; lack of capital equipment; low share of work opportunities; delays caused by clients; as well as uncertainty and unexpected climate conditions. The study concluded that; most of the contractors use all the opportunities to maximize their profits in construction projects. Most of them have survived because, they continued maintaining professionalism when it comes to work despite having low share of work/ tender opportunities. Also, corruption is one of the critical factors that affects the industry, hence hindering the contractor's growth. With the new reform and government systems, this factor has reduced to some extent as compared to how businesses were operated before, but not completely eliminated. The overall satisfaction of the profits and growth of these SMSBCs has been reduced by government reforms and policies, despite the government effort to fight corruption. When it comes to taxes and license fees, most of the contractors are irritated with constant need to pay for cost/license of operations or the presence of both withholding tax and Skills Development Levy(SDL) imposed to them when conducting business. Lastly, the study recommended; introduction of proper taxation policies; centralization of government agencies responsible for collecting annual payment from contractors should be centralized, in which only one agency should be used to supervise process; payment made by government for its construction projects to be made on time; as well as government making sure on the availability of equal opportunities for tenders in private and public sector.
AU eJournal of Interdisciplinary Research (ISSN: 2408-1906), 2021
People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal. If the publication is distributed under the terms of Article 25fa of the Dutch Copyright Act, indicated by the "Taverne" license above, please follow below link for the End User Agreement:
2017
The construction industry is one of the engines of socioeconomic growth and thus why, it's growth is important. The growth of construction industry is simultaneously to the growth of large, medium and small construction firm. The growth of these firms is not always easy nor risk free, hence making their growth interesting to study. This study intends to assess the growth trend of local building contractors for the period of 2005-2015 in DarEs -Salaam, Tanzania. The methodology employed during data collection was descriptive field survey, which involved physically administering questionnaires to local construction firms. Purposive and Disproportionate stratified sampling were used as sampling techniques, by selecting building contractors located in DarEs -Salaam. Simple Microsoft Word and Excel were used in analyzing the collected data and its presentation was done by tables and charts. Findings reveal that local building contractors lack sustainable growth particularly in terms ...
2011
The construction industry in Uganda has over the past decade experienced a boom in activities. This is as a result of the rapid population growth that is triggering the demand for housing and infrastructure. Despite the surge in activities, the industry continues to exhibit low levels of technology utilisation, contractors have continued to employ old methods of construction culminating in long construction cycles, increased costs of construction and environmental degradation. The research was conducted to take the form of a quantitative research study. The research sought the views of various respondents towards the factors hindering development of the construction industry in Uganda. Key findings revealed that the level of development in the construction industry is still very low, and the major factors contributing to this in order of priority as per the findings from the research are financial capacity, lack of research and development, economics and costs, corruption, political...
JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT, 2008
Over the years researchers have paid little attention to the performance of the clients in the building industry. Much of the research on improvement of performance of the construction industry has mainly focused on contractors and the supply chain. The performance of a client is important because any decision made will affect project success. Failure on the part of the client might lead to stress factors causing significant problems in successive stages of the project. This research is an investigation into the roles of the client to find out whether clients in the building industry in Uganda are playing their part. Due to the non‐specific nature of clients, a guided questionnaire survey was carried out among architects who normally work with different types of clients. The majority of the building clients in Uganda are individuals followed by limited liability companies. It was found out that delay by clients in paying the contractors is a major factor affecting the performance of...
International Journal of Construction Engineering and Management, 2023
Finding the essential components for enhancing construction management performance is a significant issue given the important role that the construction industry plays and the degree of performance of the sector. Therefore, the main goal of this research is to pinpoint crucial components for enhancing Tanzania's construction management performance. Management of building construction projects has been facing many challenges in Tanzania. This has led to the rise of construction complexities which have resulted in increasing delays, increasing construction scope, cost overrun, poor project quality, and generally poor performance of the construction projects. This has created a wake-up call for the country to implement different measures to improve the management of construction projects in Tanzania. But the lack of construction management skills in people involved in the construction industry has triggered the Construction Management Landscape to be difficult and to get worse. Several factors were reviewed and grouped within ten performance groups and using questionnaires, the respondents were asked to indicate the level of importance of those factors. Using Relative Importance Index (RII), MS Excel analyzed the data obtained from the respondents. The study revealed 7 key factors for improving Construction Management. Those factors are; Ability to solve problems, Project manager leadership skills, Site climatic conditions, Cost of materials and equipment, Project construction planned time, Site condition challenges, and Lack of competent staff. It is recommended that seven (7) elements identified by this study shall be considered the substantial elements by both government and private organizations for developing the construction industry and therefore they should collaborate in investing in worker capacity building for improving Construction Management performance. The results of this study give construction managers a way to use the key elements of construction management practices that have the biggest effects on construction management performance in the Tanzanian construction industry to address issues with poor project performance and delays in project completion.
International Journal of Advanced Research in Engineering and Technology (IJART), 2020
The purpose of this study was to analyze the various major factors that highly influence the development of construction technology in government projects in Bole sub city Addis Ababa, Ethiopia. In order to gather the information, the study has reviewed previous and related works in the literature part and the methodology was employed mixed method approach or both qualitative and quantitative methods of data collection and analysis. Questionnaires, Interview, FGD and document review was used as research tools to collect data. The qualitative information extracted from interview was grouped into thematic categories and analyzed qualitatively. This was supported quantitative data which was collected using questioner and analyzed using descriptive statistics. The quantitative data collected was analyzed using SPSS version 20 with correlation of the dependent and independent variables. The qualitative data was analyzed with narrative explanation. The survey result revealed that high cost of construction technology development, insufficient Resource availability for innovation, unwillingness of personnel to engage in construction technology development, tight time frames for work, fear of change within the workforce and lack of perceived return on construction Technology investment are the major factors highly influencing the Survey of Chief Factors Influencing the Growth of Construction Activities-A Proven Map http://www.iaeme.com/IJARET/index.asp 68 editor@iaeme.com development of construction technology in the study area. The study concluded that, the above factors highly influencing the development of construction technology in the study area. It is recommended that Bole sub city construction office and project Contractor should establishing relevant innovation mechanisms, the workforce should develop strong sense of innovation, encouraging domestic construction technology engineering, improving professional qualities of staff through training.
First and foremost, I would like to thank academic staff members of Building Economics Department who were the first to correct my mistakes from the research proposal to the completion of this final dissertation.
No one really knows the blood, sweat and tear that the book went through more than my courageous supervisor Ms. E. Mbuya. Her ability to strengthen weak sentences and pull out just the right adjective or adverb was truly miraculous. To her, my
Building construction industry is a very important sector which contributes significantly to the increase of any country's economy. Building construction industry in Tanzania is largely depending on the performance of building craftsmen as one among major inputs to construction projects. The main objective of this research was to identify and examine major factors that affect the performance of building craftsmen involved in building construction industry of Tanzania. The conclusion of this study was helpful in finding out appropriate strategies for improving the performance of building craftsmen in terms of cost, time and quality of work.
This study started with the general introduction. The research methodology used in included literature review from different authors related to the performance of building craftsmen; interviews where by building craftsmen, site foremen and site engineers were interviewed; questionnaires in which the questionnaires were sent to site engineers and site foremen; and observation where by construction activities were observed on sites. The study was finalized by conclusion and recommendation with respect to the analysis made after data has been collected.
Findings from the study show that materials and tools, supervision, leadership, quality, time, manpower, project complexity, external, motivation and safety were the main group of factors affecting the performance of building craftsmen in terms of time, cost and quality of work.
To improve the performance of building craftsmen in Tanzania it was recommended to ensure sustainable availability of materials on sites, increase motivations, introducing building craftsmen trade union, maintaining close supervision to building craftsmen, ensure availability of necessary safety gears, organizing strong site leadership, make regular training to building craftsmen and finally implementing expectancy theory.
APPENDIX A Questionnaire survey to site engineers and other officials concerned in building construction activities.
Interviewing guiding questions to building craftsmen
In this study a number of terms here under have been used and their meaning should be defined as described below:
Craftsmen-this refers the any person skilled in a particular craft.
Building craftsman-Is any person skilled in a particular work in the process of building construction, for example carpenter or a mason.
Construction industry-The construction industry is defined as those individuals, or groups whose principal activities involve one or more of demolition, design, production, alteration, renovation, maintenance and recycling of building works, and or of building services works, and/or of civil engineering works and/or or process engineering works.
Productivity in construction projects-Is a rate at which construction firms' produces goods or services, in relation to the amount of materials and number of employees needed.
One of the primary determinants of contractor's productivity in developed and developing countries is craft workers. Although, crafts workers are of interest to contractors, there has not been significant research on how to improve construction workers productivity. The existing research on productivity view workers simply as labour, and therefore, one of the factors of production. The implication of this assumption is that managements' objective is to maximize the efficiency with which these workers are utilized. Thus, one unit of labour is perceived as interchangeable with another. This view of inter changeability of labour leads management to focus on the work and the environment instead of the worker (Uwakweh, 1999).
Poor performance of construction workers is one of the causes of cost and time overruns in construction projects. The predominant causes of time and cost overruns are design changes, poor labour performance and inadequate planning (Odeyinka and Yusif, 1997) have shown that seven out of ten projects surveyed in Nigeria suffered delays in their execution. (Chan and Kumaraswamy, 1997) studied delays in construction industry of Hong Kong and discovered existence of poor performance of construction workers.
The performance of building craftsmen is particularly important especially in developing countries like Tanzania. The building industry in Sub-Sahara Africa has unique characteristics. To mention only a few, building construction is labour intensive as it is largely in situ; the workers are exposed to extremes of hot and wet weather conditions; the pay incentive structures are poor; the working environment is hazardous (Alinaitwe, 2007).
Labour-intensive technology is used because building construction plants and equipments are expensive and out of reach for many of local contractors who do not generate adequate incomes. The workforce uses simple basic tools that are purchased over time as funds become available. Construction workers were exposed to machine methods only occasionally, when contractors and/or owners of development hired items such as concrete mixers and poker vibrators. The use of these labour-intensive methods and rudimentary tools meant that the energy input in any task in the process of building construction was relatively high incorporated with poor labour performance (Mitullah and Wachira, 2003).
Labour-intensive technology requires much more diligence and insight than equipment-intensive construction process, and thus, labour resource became a more important input in the production phase. Moreover, production-related inactivity was not nearly as intuitively obvious in a labour-intensive project and the solutions of the inactivity are not easily found. It means that it is easy for a contractor to be lulled into a false sense of accomplishment, when the crews are all working (Kazaz et al, 2008).
Construction industries in many countries are characterized by low level of productivity. Poor performance of building craftsmen is one of the most daunting problems that drop the level of productivity in construction projects in developing countries (Alinaitwe, 2007). Despite being experiencing low productivity, the construction industry plays a significant role in the development of national economy and social development of people. Investment in construction activities in developing countries may range anywhere from 50% to 60% of planned budgets (Chahal and Emerson, 2006). In Tanzania construction sector plays a greater role in boosting the national economy, where as it contributes about 9.7 % of the gross domestic product and consecutively, it has contributed to the increase in resources production to The emphasis of this research was on labour performance on building sites. It is assumed that any effort directed to improving building craftsmen's performance will greatly enhance the country's chances to realise its development goals (Alinaitwe, 2007).
Performance of building craftsmen in this study can be examined by three major parameters which are time used by building craftsmen to perform certain work, total cost of work done by the building craftsmen and the quality of work done by the building craftsmen.
The factors that affect the performance of building craftsmen are considered to be one among major problems that hinder construction industry of Tanzania. These factors can influence cost and time overruns in building construction projects and they can also lead to low level of productivity in the rate of output and quality of work produced by building craftsmen in building construction projects. There fore there is a need to make a thorough study on those factors that affect the performance of building craftsmen in order identify, rank the factors affecting the performance of building craftsmen and finally to recommend appropriate strategies for improving the performance of building craftsmen in Tanzania.
The ultimate goal of this study was to identify and examine major factors that affect the performance of building craftsmen involved in construction industry of Tanzania, with the aim of finding out appropriate strategies for improving the performance of building craftsmen in terms of cost, time and quality of work, eventually improve quality of work, reduce time and cost overruns in construction projects.
i To rank major factors that affect performance of building craftsmen in Tanzania depending to the extent in which the factor affects the performance of building craftsmen; ii
To recognize responsible organ for finding appropriate measures for improving the performance of building craftsmen ; and iii
To make recommendations on the best practices to be used in improving the performance of building craftsmen.
i What are the factors greatly affecting the performance of building craftsmen in terms of cost, time and quality of work in Tanzania? ii What organ is responsible for finding out the appropriate measures to reduce the factors affecting the performance of building craftsmen in terms of cost, time and quality of work in building construction industry? iii
Table
9 Organization of the report.............................................................................7 CHAPTER 2...................................................................................................................8 2.0 LITERATURE REVIEW..........................................................................................8 2.1 Introduction.................................................................................................8 2.2 Forms of building craftsmen.........................................................................8 2.2.1 Formally trained building craftsmen..............................................................9 2.2.2 Informally trained building craftsmen...........................................................9 2.3 Nature of building craftsmen's employment.................................................10 2.3.1 Formal employment.....................................................................................10 2.3.2 Informal employment...................................................................................11 2.4 Performance and productivity of building craftsmen.....................................11 2.4.1 Productivity studies......................................................................................11 2.4.2 Human resource view...................................................................................13 2.4.3 Conceptual framework.................................................................................14 2.5 Workmanship and quality of work of the building craftsmen.........................20 2.6 Factors affecting the performance of building craftsmen...............................20 2.6.1 Factors that are within Materials & tools group..........................................21 2.6.2 Factors that are within Supervision group...................................................21 2.6.3 Factors that are within Leadership group.....................................................22 2.6.4 Factors that are within Quality control........................................................23 2.6.5 Factors that are within Time group..............................................................24 2.6.6 Factors that are within Manpower group.....................................................25 2.6.7 Factors that are within Project group...........................................................26 2.6.8 Factors that are within External group.........................................................27 2.6.9 Factors that are within Motivation group.....................................................27 2.6.10 Factors that are within Safety group..........................................................28 2.7 Strategies towards improving the performance of building craftsmen in construction industry........................................................................................29 2.7.1 Quality of site management.........................................................................29 2.7.2 Material ant tools control on construction sites...........................................30 2.7.3 Amount of pay and on-time payment...........................................................31 2.7.4 Systematic flow of work (planning).............................................................32 2.7.5. Supervision..................................................................................................33 2.7.6 Site layout....................................................................................................33 2.7.7 Work discipline............................................................................................34 2.7.8 Occupational education and training............................................................34 2.7.9 Working at similar activities........................................................................35 2.8 Summary...................................................................................................36 CHAPTER THREE.......................................................................................................37 3.0 DATA COLLECTION AND ANALYSIS...............................................................37 3.1 Introduction...............................................................................................37 3.2 Research instrument...................................................................................37 3.3 Data collection process...............................................................................39 3.3.1 Information collected...................................................................................40 3.4 Data analysis.............................................................................................41 3.4.1 Introduction..................................................................................................41 3.4.2 Data processing and analysis through questionnaire...................................41 3.5 Findings from actual site observation...........................................................45 3.6 Data analysis through interviews.................................................................48 3.6.1 Factors affecting the performance of building craftsmen............................48 The performance level of building craftsmen in Tanzania...........................51 3.6.4 Responsible organ for finding out appropriate measures for reducing and eliminating the factors affecting the performance of building craftsmen.............52 CHAPTER FOUR.........................................................................................................53 4.0 CONCLUSION AND RECOMMENDATION......................................................53 4.1 Introduction...............................................................................................53 4.2 Conclusion............................................................................................53 4.3 Recommendations......................................................................................53 REFERENCES.............................................................................................................56
What should be done in order to improve the performance of building craftsmen in terms of cost, time and quality of work in building construction industry of Tanzania?
1.6 Rationale and significance of the study i) This study will expose all problems which hinder the performance of building crafts men in the United Republic of Tanzania construction industry; ii) The result of the study may become the way to rectify the performance of building craftsmen on site; iii) At the end of this research, the research output will become as a source of information as reference on building craftsmen performance on construction sites or any other related topic or research; and iv) Development of strategies to improve performance of building craftsmen will increase the productivity and the performance of the construction industry in Tanzania.
Research methodology is a way to systematically solve problem. It may be understood as a science of studying how the research is done scientifically. Research methodology studies various steps that are generally adopted by a researcher in studying his research problem along with the logic behind them (Kothari, 1990)
To accomplish the research, different methods were used as a means of obtaining information and data. Through those sources, the obtained data were collected, analysed and leading to conclusion and finally giving out the recommendations. The methods used in conducting this research are discussed here under:
Various text books, journals, previous research reports, workshop papers, websites and news papers relating to the subject concerning the study on factors affecting the performance of building craftsmen that provided useful guidelines on the study were used. This was a very essential step towards recognising the gap for the research hence research.
The method involved visiting different construction sites in Dar-Es-Salaam and interviewing a sample of building craftsmen who were involved in different building crafts such as mason, painting, steel fixing, carpentry, electrical installation and plumbing installation. Besides, discussion were also carried out with other stake holders of the construction industry of Tanzania Kariakoo, which attracted the interest of the researcher. At study site level, the research used a non systematic approach in locating specific construction sites. This involved transect walk across the residential and commercial area looking for active construction sites. Since the concern of the survey was to gather information on the building construction craft people, the non-systematic approach which was used in locating sites within Kariakoo and Mwenge was found to be necessary. Within the sample of active construction sites in Kariakoo, Mwenge and its surrounding areas a total number of 20 questionnaires were distributed and 24 building craftsmen were interviewed. These respondents were those mainly working on projects developing flats and commercial and residential buildings. The respondents to be interviewed were identified by foremen or owners of development. This is because most of those in charge of the sites were suspicious of the intentions of the research .
After the data have been collected, the researcher analyzed them by categorizing them using the following techniques; coding, tabulation, and statistical techniques.
In carrying out this research, during data collection limitations were identified. The study has been limited to site management control, management influence (Contractor's management team) and interviews with those directly charged with operation on the sites (Building craftsmen).
The area (case study) for this research was Dar-Es-Salaam, specifically on the continuing building construction sites. The plenty availability of ongoing site works in Dar-Es-Salaam encouraged the researcher for the area such that data collection for the study was possible.
This research is also limited to information of performance available and carrying out interviews with those who are directly charged with operation on construction site without going deeper into theories and practicability of the activities sampling study adopted for data collection.
This research report has been organised in four chapters. They are here under described.
The chapter was about the introduction and background. I t contained the introductory part of the study, statement of the problem, aim of the study, the specific objectives and research questions; it also focused on the rationale and significance of the study, research methodology, limitation of the study, acronyms, a section for definition of terms and organisation of the report.
Chapter two: This chapter explained the literature review from different authors related to the performance of building craftsmen on construction sites.
Chapter three: This involved research methodology. It was concerned with data collection and analysis.
Chapter four: Chapter four is composed of the introductory part for chapter four, conclusion and recommendations.
Up to 18 th century the local craftsmen were fully responsible for construction activities such as building forms, spaces and style all over the world (Marten, 1995). After the 19 th century the roles that were played by the local craftsmen were formally taken over by quantity surveyors, architects and engineers (Nguluma, 2006). This is because of radical changes in building industry in aspects such as commercialisation of professions, emergency of professional criticism, allegation and frauds.
The construction industry in most developing countries is faced by serious difficulties including shortages of semi skilled and skilled building craftsmen, inadequate production of construction materials, lack of capital and poor management.
Building craftsmen are the main actors in the process of building construction (GOT, 2000), although the role of building craftsmen is not supported by any public or private institution as an important component in the construction industry in developing countries such as United Republic of Tanzania. Formal and informal trained building craftsmen contribute substantially to the construction of buildings.
The services being rendered by semi skilled and skilled building craftsmen play a significant role in building construction which suggests that integration of building craftsmen skills and the formalised professional services could realise quality services in the construction industry.
This chapter was of essential important in accomplishing this study. It includes data collection, data analysis and giving out findings of the study. Different methods were attempted in data collection; these methods were Questionnaires in which the questionnaires were distributed to different stakeholders of the building construction industry and then filled questionnaires were collected back for making data analysis, on the other side interviews and observations were also used as methods for data collection The data collection based on identifying and ranking major factors which affect the performance building craftsmen in the building construction industry of Tanzania. This paved the way to provide either appropriate measures or probable recommendation for the measures towards eliminating all of the factors which negatively affects the performance of building craftsmen in building construction industry.
The aim of data processing phase was to summarize information obtained from questionnaires distributed to different people, interviews and observations; this involved the descriptive tables or figures. The data and information collected in this study were mainly summarized by tables or figures and some of them were summarized by statistical descriptions.
In this chapter major conclusion towards research questions and objective were
presented. Finally the chapter ended with recommendations that present solutions to the problems which hinder the performance of building craftsmen so as to improve their performance during execution of building construction activities. Main objective of this research was to identify and examine major factors that affect the performance of building craftsmen involved in construction industry of Tanzania. However, chapter three analyzed major findings of the surveyed questionnaires, interviews and observations. It was also used to answer research questions.
Building craftsmen can be divided into different forms depending on the subject matter of the study. For the purpose of this research building craftsmen are going to be divided mainly into two forms which are; formally trained building craftsmen and informally trained building craftsmen.
Building craftsmen receive their education in the form of formal training in vocational schools, technical colleges and attendance at workshop complemented with field activities. Training on its own part is a process of bringing a person to a deserved state of efficiency by instruction and practice. Training has been defined as the systematic development of the attitude, knowledge and skill behaviour pattern; required by an individual in order to perform adequately a given task or job. Putting it differently, it is an activity, which is concerned with making employee more articulate and efficient in their performance of their current tasks or preparation for a new type of job to meet the dynamic needs of the organisation (Cooker, 2000).
It is generally believed that most developing countries are characterised by abundant supplies of building craftsmen. However, they are plagued with scarcity of skilled building craftsmen. Training of construction craft workers is not very common in developing countries, and when they are available, they may not be adequate. T o improve the situation, informal on-the-job training are not well developed and not common. The lack of serious construction craft workers training can be attributed to the fact that contractors even in the developed countries take a short term view of craft training. Another reason is the fluctuations in the construction projects. Construction crafts workers, once they complete their tasks on a project are laid off, and hence, must move to another project. As a result, construction workers tend to identify more with their trades than with construction firm. Also, contractors keep workers on their payroll only when they have projects. The culture of contractor's organisations or even contractors being involved in formal training of the various skills required in the industry is non existent (Uwakweh, 1999).
In this form of building craftsmen, knowledge is acquired through Informal skilling, which includes both informal skills training and informal apprenticeship, is an adhoc and unsystematic method of learning skills on-the-job which is received within the context of day to day production activities (Middleton et al., 1991). It mainly involves learning via observing and doing and is largely confined to initial employment training with limited continuation of training and skills upgrading. Informal skilling is geared towards the transmission of existing practices without or with minimal external input (e.g. from colleges). The implication of this is that the master's ability to train is limited to his current skill and knowledge and this often results in low productivity (Ziderman, 2003).Informal skilling is common in the construction sectors of many developing countries e.g. Philippines, Indonesia, Egypt, India, Mexico and Brazil (International Labour Organisation, 2001;Alwi et al., 2006). Haupt et al. (2005) reported that among the contractor employees in the Western Cape province of South Africa, 31% of the craftsmen, 54% of semi-skilled operatives, and 68% of the general operatives are trained informally.
Informal skills training and apprenticeship has thus become common, especially among young people who, for various reasons, are unable to progress up the academic ladder; or gain admission to vocational training institutions; or those of all ages who cannot find employment in the formal sector (Kent and Mushi, 1995;Johanson and Adams, 2004).
Additionally, informal skills training is attractive in developing nations because it is self-financing in that it takes place without any funding from budget-constrained governments or formal levy funding by relying mainly on user fees or low wages for the apprentices during training (Ziderman,2003). Moreover, informal skills training and apprenticeship has expanded because many of the existing formal training institutions are ill-prepared to equip trainees with the skills needed to operate in an informal sector which is fast becoming the dominant employer (Kent and Mushi, 1995;Ziderman, 2003;Johanson and Adams, 2004).
Generally there are two categories of employment for the building craftsmen. In which, the first category is formal employment and the other one is informal employment.
Formal employment can be defined as employment where construction workers are permanently employed with proper form of contract, worker benefits and social protection.
Informal employment as conceptualized by (WIEGO, 2002) and (ILO, 2002) is defined as employment without secure contracts, worker benefits, or social protection.
Meanwhile according to (Mitullah and wachira, 2003) Informal labour is defined to include all construction workers who are employed on a casual or temporary basis without any proper form of contract, as well as those who work for themselves either alone or in small groups. The terms and conditions of employment are not regulated in any way and hence the workers have no protection from the law against dismissal and no social protection against sickness, old age or incapacity to work.
In some low-income countries the vast majority of construction labourers have always been employed informally. In others, the number of such workers has increased dramatically in the past few decades, as competitive pressures have forced contractors to shed their directly employed labour force in favour of 'outsourcing' their labour requirements. Most labour are now engaged through subcontractors and other intermediaries. Subcontractors, who are themselves employed for short periods of time, invariably employ workers on a short-term, often daily, basis. They generally avoid issuing the workers with written contracts and registering them with relevant authorities, in order to avoid the on-costs associated with employing labour. Indeed, the evasion of these additional costs is often the motivation for outsourcing in the first place (ILO, 2002).
The primary concern of contractors in developed and developing countries is with craft workers and how to increase their productivity. Although, this is of interest to contractors, there has not been significant research on how to improve construction workers productivity. The existing research on productivity view workers simply as labour, and therefore, one of the factors of production. The implication of this assumption is that management's objective is to maximize the efficiency with which these workers are utilized. Thus, one unit of labour is perceived as interchangeable with another. This view of inter changeability of labour leads management to focus on the work and the environment instead of the worker (Uwakweh, 1999).
The assumption of this engineering view of worker is that the worker possesses the necessary abilities (mental and physical) to successful perform a given task. Thus, management can enhance worker performance by providing the necessary equipment, materials, tools, instruction and the environment that is conducive for expected level of performance. As a result, performance is indicative of the effort expended by the worker due to resource provided by management.
According to (Uwakweh, 1999) performance of building craftsmen is influenced by the four variables. The duration of effort the worker is willing to exert in the task, the intensity of the worker's effort, the effectiveness with which the worker's effort is combined with technology and other resources, and the efficiency of the worker's effort. The proportion of time the worker is engaged in the productive work during wok period is the duration of the worker's effort. This time may be influenced by the availability of resources and the worker's motivation. Similarly, it may also provide an insight on worker's ability. The effectiveness with which a worker's effort is combined with technology and other resources is a measure of degree to which the productive potential of technology and other resources has been utilized. As an illustration, a worker can move bricks either by wheel barrow or a forklift. In the later case, the worker's effort has been combined much more effectively with the available modern technology. The efficiency of a worker's effort is a measure of the quantity of the acceptable quality output provided by a worker as a result of effort expended. It is possible for a worker to expend effort very intensively over a period of time, but if the quality of work is poor, then the worker's efficiency and performance will be low. On the other hand, a worker may take extreme care to produce high quality product, but, because of the time expended in producing this high quality product, not enough quantity is produced. In this case the worker's efficiency and performance are low.
This is true if the quality of the individual's work is far more superior than required by the task. Using rough carpentry as an illustration, it is not necessary to measure a piece of lumber to the same tolerance as we would in finish carpentry.
From this brief discussion, it is obvious that, management has significant impact on these variables. It has been found that effective planning and scheduling of The basic deficiency of the engineering view is the assumption that units of labour are interchangeable. In economics, the assumption of interchangeability is valid because it permits economic analysis. However, when this concept is applied to labour it falls short. This is principally because it assumes that all workers are created equal. That is the problem with the engineering view. Human beings are basically different. Some workers are more endowed than others and therefore produce quality work due to innate abilities, training and motivation. Because of this difference, some workers produce more with better quality than do other workers. Considering human differences, the engineering view falls short as a useful analytical tool. Thus, it is suggested in this research that it is useful to view workers as human resources.
In the human resource view of workers, each unit of labour is viewed as an individual, and differences between individual workers are important. When a constructor seeks to hire a mason he does not want to hire just any mason; rather the constructor wants to hire the best mason in the market. Thus, a constructor will want to hire the mason who will do a better job than any other mason. In the human resource view, the mason is viewed as an investment. The constructor can enhance the worker's performance through training programs or informal on-the-job-training.
In the human resource view of workers, the worker interacts with his job and attempts to attain some control over his job. There are benefits and costs associated with each job and each also places physical and mental requirements on the worker.
Psychological factors determine how a worker responds to his job. Due to individual differences, a worker may respond positively in a situation while another will respond negatively. Not only are there differences between workers response to a specific job, but a worker will respond differently to the same job at different times because of the change in the workers need. The degree of autonomy, significance, skill variety and feed back contained in the job affects how a worker responds to the job. Other factors such as the opportunity to acquire new skills, on-the-job training will also influence the workers response to the job.
Some dimensions of work context will also influence worker's response to a job. As an example, pay, promotions, recognition, and working conditions are important contextual factors. Pay includes all elements of compensation. The amount of pay, method of payment, and equity will influence the worker. In the same view, the opportunity for promotion, whether it is fair or not will also influence the worker.
Interpersonal dimensions of the job are important influences. The level of supervision that a worker receives including such factors as the supervisory style, human relations, all influence the workers response to the job. The influence of co-workers is also important. The competence, helpfulness, and friendliness of co-workers and the policies of the firm's management also impact on the worker. Therefore, based on human resource view, the individual worker is the primary unit of analysis and what the worker wants from the job is an important question. As a result, psychological factors are important in analyzing and predicting worker performance.
Studies into worker performance in other industries apart from construction industry resulted in the development of the expectancy theory of worker motivation and performance. This model was developed by (Vroom, 1964) and (Parter and Lawler 1967). The model is now a primary model that is used in the analysis of worker performance. A detailed discussion on this model can be found in (Vroom, 1964). The first attempt to use this model in the construction industry was done by Maloney (1985). However, his emphasis was on developed nations. This study is the first effort in suggesting that this model can be used in the developing countries.
This framework is based on the expectancy theory of worker motivation, performance and satisfaction. This framework is shown in figure 1. People engage in work to accomplish something for themselves. They have a particular job that they have to complete. By doing the job they receive some rewards which they hope will satisfy
Expectancy, which is the link between an individual's expenditure of effort and his performance of a task, is defined as the individual's belief that he can convert his effort into performance of the specified task. In essence, it is the persons belief that his effort can be expected to lead to successful performance. As a result, expectancy can have values between 0 and 1. An expectancy value of 0 indicates that the worker perceives no chance of being able to perform the task if he tries to do so. Conversely, an expectancy of 1 indicates that the worker believes that by exerting the effort, he will perform the task every time he tries (Vroom, 1964).
Instrumentality, on the other hand, is the relationship of performance of the task to the potential outcomes that may be received by the worker as a result of performing the task. It may be defined as the workers belief that his performance of the task will lead to the receipt of a specific reward or outcome. An instrumentality of 0 indicates that there is absolutely no chance that the worker will receive the specific reward if he performs the specified task. An instrumentality of 1 indicates that the reward will be received every time the task is performed (Vroom, 1964).
Rewards or outcomes are evaluated by its ability to satisfy the recipient's needs. This ability is the valence of the reward and is defined as the anticipated satisfaction associated with the specific outcome. The satisfaction can only be determined after the outcome has been received. Thus, it is possible that a workers valance may be, positive, negative or neutral. When it is neutral it is viewed as neither having the ability to enhance nor prevent future satisfaction. An outcome that is negative on the other hand is perceived as eliminating current and preventing future satisfaction; while a positive valence indicates that the worker perceives the outcome as having a great ability to satisfy his needs (Vroom, 1964).
Thus, the expectancy theory indicates that the more attractive the performance of a task, the more motivated the worker will be to perform it. Attractiveness is the expected value of anticipated satisfaction of the rewards or outcomes associated with the performance of a task. The greater the attractiveness, the stronger the motivational force on the worker (Parter and Lawler 1967).
One advantage developing countries have is to learn from developed countries and implement those lessons that have been proven to be effective. One such lesson from the United States is the realization that the development of the industry work force is a partnership between the stakeholders. Essentially, it is a partnership between the owners of construction and the contractors. If the owners expect quality projects to be completed on time and under budget, then they should be willing to work with contractors in developing the workforce required. (Uwakweh, 1999) has proposed that this partnership may be made possible through the organization of Local User Councils (LUC) or other similar arrangements that will bring all stakeholders together.
Through this council, the industry can develop programs that will enhance the development of quality workforce. With a pool of quality workers in place, the next concern is how to motivate them to perform at an acceptable level.
The expectancy theory which was presented conceptually has three major variables, expectancy, instrumentality and valence that are critical in managing construction workers performance. Of these three variables, management has influence over expectancy and instrumentality, while the worker has influence over valence. The first important factor in implementing the expectancy model is the need for the industry or the Local User Council member to conduct a study to determine what factors are important to these workers and what they want from their job. This is where the engineering view of workers as a factor of production differs from human resource view which treats workers as being different from each other and come to jobs hoping to satisfy some needs.
Because expectancy deals with worker's belief of being able to perform, contractors must seek to design jobs on sites that workers can accomplish. They should also provide these workers with tools, training and effective direction on site so that they can do their task. As an illustration, no matter how much belief a carpenter has on his ability to measure and cut lumber, if the carpenter is not provided with adequate cutting saw, it is virtually impossible for him to perform that task successfully. Further, there are some workers who may have all the tools but need more instructions than others. In essence, management must focus on what workers need to perform their tasks.
Workers come to their jobs expecting that if they perform they will receive some rewards. Therefore, management must make rewards contingent on performance. One of the problems in the developing countries is a high degree of nepotism and subjective management. It is not uncommon for foremen or even managers to reward persons they know more than the others, even when they have not performed nearly as well as the others. The first assumption that is made in this recommendation is that wage rate must be published or provided to the worker before engaging him in the work. In other words, the rate should be well defined and not be a secret. Other types of rewards, in addition to adequate wages could be retirement benefits, medical benefits, job security and paid vacations. These are examples, and may not be valid in all instances.
Another factor that should be treated with care is equity. When workers perceive that the reward system is not equitable and it is not related to performance, then it will act as a de-motivator. Rewards can be extrinsic or intrinsic. Rewarding workers may be as simple as praising workers for high performance. Constant use of negative extrinsic rewards such as criticism for poor performance may inhibit workers in performing effectively.
This is the factor that clearly distinguishes human resources as an effective method of motivating workers. If we define motivation as the force that will drive an individual to engage in behaviour, then, our goal should be to determine the forces that will drive workers to perform. To determine the forces, it is recommended that contractors should study workers either by survey or interview to identify what workers value most. While it is virtually impossible to have a system that will cater to each individual worker, this system however, will assist in determining the set of rewards that workers value. What is important is determining the rewards that can be implemented and linked to performance. For example, in the United States, wages are not motivational because workers must receive pay for showing up for work.
Therefore, the concern in the United States is for those rewards that encourage worker performance beyond the minimum expectation. As an illustration a paid day off from work because of high performance may be more rewarding to a worker then extra pay. This is because; the worker may use the paid day off to attend to his personal needs or other obligations. While extra pay may be good, in this instance it fails to allow this worker to meet these needs.
Despite being the main actors in the building construction process, workmanship of building craftsmen especially in developing countries is generally poor. For example, most of houses surveyed on a study done by (Nguluma, 2006) had poor finishing which reflects that building craftsmen are not meticulous while doing finishing;
Obvious mistakes were noted on plastered walls in terms of surface levelling, windows and door canopies; In other cases it was noted that there was a problem of construction roof in a proper way for example, fixing roofing sheets without wall plate; On the other side fixing of windows and doors was a problem because in most cases door frames and windows were not properly aligned; building craftsmen also use certain building techniques without having the knowledge of why it has to be used in that particular way; and according to the same study one of the reasons leading to poor workmanship is limited opportunities for the building craftsmen to obtain access to formal training which can improve their building construction skills.
There are several factors, which can influence the performance of building craftsmen in construction industry. In this study those factors have been classified in ten groups as mentioned here under: Kenya (Guhathakurta and Yates, 1993;Lim and Alum, 1995;Olomolaiye et al, 1996).
Tool and equipment shortages also have a high effect on building craftsmen performance. Tool and equipment shortages have a high effect in the performance of building craftsmen in the US, UK, Indonesia, and Nigeria (Guhathakurta et al, 1993;Olomolaiye et al, 1996). This result might be justified, as labour needs a minimum number of tools and equipment to work effectively. If there is lack of equipment and/or tools, its performance will decrease.
Unsuitability of materials storage location has an average effect on building craftsmen performance, this fact was supported by Thomas and Sanders (1991), who stated that size and organisation of materials storage location have a significant impact on masonry performance. This result is justified as building craftsmen needs more time to fetch required materials from unsuitable storage locations, which negatively affects its performance.
To determine factors affecting the performance of building craftsmen, the building craftsmen interviewed were asked to identify major factors affecting the performance of building craftsmen in the building construction sites.
All supervision factors have a high impact on building craftsmen performance, and are classified as follows: drawings and specifications alteration during execution; inspection delay; and supervisors' absenteeism.
Drawings and specification alteration during execution is the most important factor in supervision factors group. This can be supported by Thomas (1999), who stated there is a 30% loss of efficiency when work changes are being performed. This can be interpreted as changes of specifications and drawings that require additional time for adjustments of resources and manpower so the change can be met. Building craftsmen morale is also affected by extensive numbers of changes.
Inspection delay is the second important factor in supervision factors group, and it also has a high impact in the US, UK, Nigeria, and Indonesia (Guhathakurta et al, 1993-Olomolaiye et al, 1996. This can be described as, work inspection by a supervisor is an essential process to proceed in work; for example, as contractors cannot cast concrete before inspection of formwork and steel work, inspection delay contributes to delays in work activities Supervisors' absenteeism is the last factor in the supervision factors group. This is not surprising in Gaza Strip projects, as absenteeism of supervisors stops work totally in activities that require attendance of supervisors, such as casting concrete and backfilling.
This factor in this group can be divided into three categories as follows; Lack of building craftsmen surveillance; Misunderstanding between labour and superintendents; and lack of periodic meeting with building craftsmen.
Lack of building craftsmen surveillance has a high effect on building craftsmen performance, this can be illustrated as, lack of building craftsmen surveillance increases building craftsmen mistakes at work, as well as delaying corrective action for these mistakes. (A. Enshassi et al. 2007) Misunderstanding between building craftsmen and superintendents has a high effect on the performance of building craftsmen. This is justified, as misunderstanding between building craftsmen and superintendents creates bad relations between them.
Such misunderstandings have adverse effects on building craftsmen mood, and consequently decrease its performance.
Finally, lack of periodic meetings with building craftsmen are not considered to be as instrumental as other factors on building craftsmen performance. This fact might be justified, because building projects within the Gaza Strip are small and problems facing work can be discussed at any time with superintendents; therefore there is no need for periodic meetings with labour to discuss these problems. (A. Enshassi et al.
Quality group can be further divided into three categories which are as follows:
Inefficiency of equipment, poor quality of raw materials, and high quality of required work.
As the performance rate of inefficient equipment is low, and this consequently has an adverse impact on building craftsmen performance depending on this equipment. The type of equipment also affects building craftsmen performance; for example, new and modern equipment has a high performance rate, while old equipment has a low one, and is subject to large number of breakdowns.
Poor quality of raw materials is one among the factors which affect the performance of the building craftsmen, this fact might be justified, as the time needed to build with materials of poor quality is greater than the time needed to build with high quality materials. Additionally, wastage of materials of poor quality is high, particularly during handling. Furthermore, using materials of poor quality leads to poor quality work, which is consequently rejected by the supervisor.
Quality of required work has an average impact on building craftsmen performance, in this fact the client can decide the quality of the output he needs, depending in his financial position and the building craftsmen has no choice than doing what the client needs, also as time required to finish work depends greatly on allowed tolerance of required work; i.e. when the tolerance of required work is very low, labour work slowly in order to avoid unacceptable mistakes.
There are five factors affecting the performance of building craftsmen related to time , these are: working for 7 days per week without holiday; misuse of time schedule; method of employment; increasing workforce to accelerate work was and work overtime.
Working 7 days per week without holiday has a high effect on building craftsmen performance, while working additional hours during the working day has an average effect. (Hinze, 1999), state that working additional days and hours has a negative impact on building craftsmen performance. This is not surprising, because working additional days and hours creates an adverse effect on the motivation and physical strength of building craftsmen, thus decreasing their building craftsmen. However, the impact of working additional hours for a short period may be not noticeable, or nonexistent.
Misuse of time schedule has a high negative impact on building craftsmen performance, as good use of time schedule leads to many advantages such as continuous flow of work; reduced volume of rework; minimisation of confusion and misunderstanding.
Method of employment also plays a greater role in affecting the performance of building craftsmen. For instance sing a daily work system instead of a unit rate system has positive effect on building craftsmen performance, this can be verified, as the building craftsmen desire to work by unit rate system to earn more money. Therefore building craftsmen works too hard to finish the greatest volume of work when working by the unit rate system. (Enshassi, et al. 2007) Increasing the workforce on the construction site has a moderate effect on building craftsmen performance; this can also be supported by Hinze (1999), who mentioned that increasing the workforce on a construction site has an adverse impact on building craftsmen performance.
Normally when increasing the workforce on a construction site causes overcrowding of labour and interference between labour and gangs, which consequently reduces their performance.
There are five factors in the group related to manpower. The factors negatively affecting the building craftsmen performance are: lack of building craftsmen experience, followed by building craftsmen disloyalty, misunderstanding among building craftsmen, lack of competition and ageing building craftsmen Lack of building craftsmen experience has a very high effect on their performances, (Paulson, 1975), found that experience of the building craftsmen affects building craftsmen performance. This is also supported by (Heizer and Render, 1990), who confirmed that experience of workforce affects job site performance. Always experience improves both the intellectual and physical abilities of building craftsmen which consequently increase building craftsmen performance.
Building craftsmen disloyalty has high effect on building craftsmen performance;
Unfaithfulness of building craftsmen reduces its performance (Nguluma, 2006) found that sometimes when building craftsmen are given cement for the case of plastering they do not use the proper ratios of mixing of sand and cement. Instead they save the cement and resell it; this automatically leads to poor quality of work.
Furthermore, misunderstanding among building craftsmen has a negative effect on building craftsmen performance. (Enshassi, et al. 2007) justified, as misunderstanding among building craftsmen creates disagreement among building craftsmen about responsibilities and work bounds of each building craftsmen, which leads to a lot of mistakes in work, and consequently decreases building craftsmen performance.
Lack of competition can also reduce the performance of building craftsmen, for example in specialist works such as tile works if there are very few competent craftsmen hence this make the available crafts men to do works below their capacity because they don't have substitutes.
Ageing of building craftsmen has an adverse effect on the performance of building craftsmen. (Heizer and Render 1990) support this fact citing that the age of the workforce affects job site productivity, that is, as building craftsmen age increases speed, agility, and strength decline over time and contributes to a reduced building craftsmen performance.
The most important factor in this group is working within a confined space, followed by interference; construction method; and type of activities in project.
Working within a confined affects negatively the performance of building craftsmen, this can be supported by (Thomas and Sanders1991), in which it was reported that one of the common reasons for low performance of building craftsmen is working within a confined space. This can be explained, as confined spaces reduce free movement of building craftsmen, and consequently reduce their performance.
Interference has an average impact on building craftsmen performance. Interference also has a significant impact on building craftsmen performance in the US, UK, Nigeria, and Indonesia (Guhathakurta and Yates, 1993;Olomolaiye et al, 1996).
Interference between gangs and building craftsmen is caused by mismanagement on construction sites, with steel fixers suffering more of this, possibly because they are more dependent on other trades. For example, if the carpenters have not completed the formworks, steel fixers will have to wait before fixing the reinforcement rods.
Construction method and type of activities in the project are not considered to be as instrumental as other factors in reducing the performance of building craftsmen. This can be supported by (Thomas and Sanders, 1991), who found that construction method and project features have a high impact on building craftsmen performance. This can be explained as follows: because building projects within the Gaza Strip are not complex and are small in size. Therefore activities in different projects largely have the same features, and there is no major difference between methods used in construction.
The factors within external group are weather changes and augmentation of government regulations related to the construction sector.
Weather changes have negative impact on building craftsmen's performance, (Thomas and Sanders, 1991) support this in their study of factors affecting productivity in the US. The temperature in the Gaza Strip is moderate; therefore, increase and decrease of temperature have a low effect on building craftsmen performance. However, adverse winter weather such as winds and rains reduce building craftsmen performance;
particularly on external work such as formwork, steel work, concrete casting, external plastering, external painting, and external tiling. Adverse weather sometimes stopped work totally.
Augmentation of government regulations related to the construction sector affect negatively the performance of building craftsmen but is not considered to be as instrumental as other factors. This might be justified by (A. Enshassi et al. 2007) who stated that, within the Gaza Strip, where government regulation of construction projects has been subjected to minor changes only during the last years.
There are four factors under the group related to motivation. These factors are: payment delay; lack of financial motivation system and lack of labour recognition programs; non-provision of transportation means, lack of places for eating and relaxation; and lack of training sessions.
Payment delay has a high effect on building craftsmen's performance (A. Enshassi et al. 2007). This can be explained, as payment delay has a very bad effect on building craftsmen mood, and consequently decreases its performance.
Contractors believe that lack of financial motivation system has greater negative impact on building craftsmen performance than the lack of building craftsmen recognition programs. Motivation is essential to building craftsmen, as it gives site workers satisfaction such as achievement, sense of responsibility and pleasure of the work itself which can automatically improves their performance.
Non-provision of transport means, places for eating and relaxation also affect the performance of building craftsmen and is considered to be as instrumental as other factors affecting building craftsmen performance. According to (Lema, 1995), nonfinancial benefits such as transport, meals, and uniforms have a high effect on building craftsmen performance.
Lack of training, according to (Nguluma, 2006) is one of the reasons leading to poor workmanship of building craftsmen. Unlimited opportunities for building craftsmen to obtain access to formal training can lead to improvement in their building construction skills hence high performance.
There are five factors under the group related to safety. These factors are: accidents, violation of safety precautions, insufficient lighting, unemployment of safety officer on the construction site, and noise.
Accidents have a high impact on building craftsmen performance; this can be supported by (Thomas and Sanders, 1991), who stated that accidents have a significant impact on building craftsmen performance. There are 3 types of accidents:
• Accidents resulting in the death of injured building craftsmen; this type of accident leads to total stoppage of work a number of days;
• Accidents that cause an injured building craftsmen to be hospitalised for at least 24 hours; this type of accident decreases performance of the gang in which this injured building craftsmen was working; and
• Small accidents that result from nail and steel wires; these affect productivity in only a few cases.
Insufficient lighting has an average impact on building craftsmen performance. This fact is justified, as building craftsmen needs sufficient lighting to work effectively, and consequently, insufficient lighting has a negative impact on building craftsmen performance.
Unemployment of the safety officer on construction site is considered to be as instrumental as other factors on affecting the building craftsmen performance.
It should be clear understandable that employment of a safety officer on construction sites helps the building craftsmen to understand the required safety regulations, and then to follow them. This prevents, or at least reduces, the number of accidents, which consequently improves building craftsmen performance.
construction industry.
Improving building craftsmen performance could be best carried out by means of development in management quality. Namely, the principal difference in building craftsmen performance is the management influence. Stages of estimating construction time and cost reliably, where the knowledge of building craftsmen performance takes a considerable part, are the main items of successful management understanding. In the study of Sanvido (1988), ineffective management was cited as the primary cause of poor performance rather than unmotivated or unskilled manpower. One of the primary means of rising building craftsmen performance through management is to procure and control adequate working conditions in which, building craftsmen performance in construction is greatly affected by working conditions that change from project to project. A good estimate of building craftsmen performance requires a careful analysis of working conditions and their impact on quality of work produced.
Under inadequate working facilities, no employer can expect that building craftsmen satisfactorily work. Managers, therefore, should be aware that even highly motivated and skilled operators, working under poor conditions, will not continue to produce quality work. Investment in working facilities will not only enhance operatives' performance, such as high technology equipment and replacing immediately broken, lost, or stolen tools and machinery with the new ones, but also can be used as a potential contributor in placating other concerns such as safety on site. A project manager in the present study has expressed that even working clothes are effective motivators for building craftsmen.
To be able to obtain a high project performance, however, it has a great importance to get a building craftsmen employer or building craftsmen -manager relation based on mutual trust in attaining coordination and improving quality of work. In other words, the workforce and management team share a strong and positive relationship in terms of building craftsmen performance, and, thus, an evaluation of labour resources requires joint consideration of operatives and management. For this purpose, a flexible management style and a simple organizational structure should be established in construction. Central management, lack of confidence in employees, and formalities are the obstacles to this type of management. In this point, communication is a vital aspect of organizational life (Cornik, 1999). There fore there should always be a positive dialogue between professional site staff and building craftsmen, and these staff should also keep the building craftsmen motivation high.
On the other hand, conflicts are predictably greater in number in industries such as construction with its creation of human relationships, and it is impossible to make it high continually, since morale is a concept that has different perspectives. In such cases, foremen, who constitute communication between construction workers and managers, should be seriously interested in every kind of building craftsmen problems.
The other choice that can be applied to get a building craftsmen performance boom by management is the selection of the right people to control certain functions. The qualification level of managers and supervisors is one of the vital elements determining the level of building craftsmen performance. Experienced staff leads to proper coordination of resources of the project. Particularly in the international construction tenders, an attention is paid to the qualification of technical personnel rather than labour employed in project since the personnel is the most important factor that assures good performance of workers (Kazaz et al, 2008). Managerial errors of site engineers and managers who lack proper experience, knowledge, and management skills can negatively affect building craftsmen efficiency.
Material control involves choice of standard material source, testing of samples and conformity to standards. An exhaustive and detailed proforma is evolved and rigorous testing and inspection are carried out. This is one of the most critical activities as the quality of the materials used goes a long way to achieve the objectives of attaining durability of services and user satisfaction (Chahal and Emerson, 2007). Contractor must ensure that machinery meet the requirement of the project. Regular surveillance by quality assurance experts ensures that the proper methodology and technology is applied to the work which can promptly improve the performance of building craftsmen.
Moreover, documented quality assurance programme shall be implemented. The establishment of the programme shall include consideration of technical aspects of the activities effecting quality. The programme shall be established at the earliest time consistent with the schedule for accomplishment of project objective. The programme shall provide for the planning and accomplishment of activities affecting quality under suitable controlled conditions including the use of appropriate equipment, suitable environment conditions and assurance that prerequisites for the given activity have been satisfied. The programme shall provide for special controls, processes, test equipment, tools, and skills to attain the required quality and for verification of quality. Quality in construction is related to that of conformance to various codes and specifications listed in the contract document. But to ensure that quality is being provided one has to look at the actual personnel who are executing the work. Unless the building craftsman is motivated, trained and has proper tools and materials, he will not be able to give the actual quality which was initially intended. No amount of planning, designing and lay down of specification can help you achieve the quality unless the actual workers on ground provide it (Chahal and Emerson, 2007).
Remuneration is seen as the most important reason of why a building craftsman has to work in a job. Because it both meets the physiological needs that are the most basic requirement of people, and gives esteem in a society. The amount of pay and on-time payment is the most vital factors required to meet the first hierarchy need of Maslow.
Building craftsmen, for example, will probably quit the job if a higher wage is offered by another firm. Despite Hertzberg's argument that money is not a satisfier and thus not a motivator, the present survey coupled with previous works such as (McKenzie and Harris, 1984), (Price, 1992), (Ogunlana andChang, 1998), and(Yisa et al. 2000) seems to indicate the contrary. In these studies, it is supported the contention that money is one of the most powerful motivators of construction workers, while low pay levels are a major source of discontent to many construction operatives. Hence, with inadequate wages one cannot expect operatives to perform a challenging task competently. However, it does not mean that determining a fair level of pay always causes high building craftsmen performance. By another view, in the construction industry like many other sectors, pay level is usually not a motivation tool determined by taking individual performance into consideration. This is actually not practically applicable. The production performance levels of all workers are accepted as similar, and thus, equal wage levels are paid. Timely payment is also one of the primary principles of any working agreement. Whilst adequate working facilities can reduce to some extent the demotivating effects of low levels of pay, delay in payment simply cannot.
It is almost obvious in construction management that a project may be regarded as successful if the building is completed on time, within budget, to the specified quality standards and overall client satisfaction (Kazaz et al, 2008). Careful planning of human resources is the foremost agent in fulfilling these constraints. Poor planning, however, can adversely affect building craftsmen performance through the need for rework and can result in lost time for building craftsmen, since they are often paid on work done satisfactorily alone. Most workers take considerable pride in the work they have accomplished that can be seen from the very start of construction through completion. For building craftsmen to go back again and take apart what has been completed can be extremely frustrating and can cause them to put forth less effort for the remainder of the work.
Resource levelling is of paramount importance in planning as well. Changes in the number of building craftsmen during project should follow a gradual move since rapid changes can cause organizational mistakes and make adaptation process difficult among both building craftsmen and management staff. Building craftsmen efficiency is affected by deviations from the normal flow of work. That is, building craftsmen performance can be estimated by analyzing, how the quality of work deviates from which has been planned.
To follow-up and supervise building craftsmen while working is a vital aspect of any organization because poor supervision of building craftsmen it can result in extensions of project time and cost, and the quality on site is controlled through inspection of the work completed by the building craftsmen.
Supervisor's incompetence is another phenomenon; questions of workers about tasks should be accurately replied by inspectors as quick as possible; waiting for the answer is so bad for the project in terms of authorities and images of these staff, reducing the work quality.
Supervisors' communication with building craftsmen has a supreme importance as well. It is a fact that building craftsmen feel embarrassed and pressed with the existence of tight audits. Multiple tiers of field supervision reduce overall building craftsmen efficiency.
To control building craftsmen periodically by making them aware of the existence of inspectors rather than to wait close to them without leaving is the most favourable method of supervision. The technique mentioned should not be interpreted as poor supervision, but be perceived as a fundamental principle of building craftsmen management. In this point, piece-work or task basis supervision will be ideal. On the other hand, a smaller span of control has been shown to foster worker's interference (Thomas et al.1990).
Layout can influence building craftsmen performance and enhance space management capability. It defines the location of the tools and supporting utilities for optimum product flow, and thus has a direct impact on the facilities' time and cost of construction. In this context, the location of the management office has a strategic importance as well as building craftsmen dormitories on site; especially there are many shifts that may cause loud noise and thus a possibility to sleep; hence high building craftsmen performance.
One of the primary conditions for improving systematic and quality working habits is to have a complete work discipline on site. Discipline can be defined as a concept that determines the human being behaviour by means of reward or punishment. This concept becomes more important in Turkey, since workers in the construction sector are still composed of individuals coming from the rigid regions of patriarchal society (Kazaz et al, 2008). The basic rule of keeping discipline among the building craftsmen is that the work discipline of management staff is at the top level. It has a vital aspect that these staff members start working before the workers and finish it after them. Site managers should also pay attention to using their authority on workers according to a personal plan, which has to conform to their characters. However, work discipline will not be able to be kept in any case, if workers have not any job responsibility or working ethics. In this situation, a project will likely be unsuccessful, if site manager does not take any precaution.
Vocational education, particularly in developing countries, is the total of activities, which enable the reasonable employment of unskilled labour by educating and directing them to vacant fields of labour market, to regulate and control those who come from farming and do not have any continuous working habit. Poor performance and high costs in every branch of industry are due partly to low levels of training.
Lack of occupational education in construction is now a reality in many countries around the world. For instance, there is currently a lack of formal training in construction in the US -the lowest of any major sector of the economy (The construction...1997). According to Allmon et al. (2000), this lack of job training is due to the increased percentage of non-union work. Increasing levels of non-union journeymen naturally cease any educational process.
In a business environment, where little educated people are employed as craftsmen, workers are mostly educated only by the apprentice-craftsmen relationship on site, but this type of relation, which is in fact essential under normal conditions, becomes meaningless, since craftsmen are also uneducated. Inexperienced workers bring about large amounts of resource waste such as material, equipment, and tool until they are trained, and thus the triple constraint of project, i.e. cost, time, and quality, is directly influenced.
The most sensible solution may be occasional short training programs or day-release courses and seminars in educational establishments in support of firm managers, employers' associations, trade unions, societies of engineers and architects, universities, and governments. This solution, however, has a serious disadvantage.
Whether or not construction companies undertake the financial loan of their current building craftsmen is a big question mark because the workforce in construction is generally highly mobile. For this reason, contractors are often reticent to invest capital to train those who may soon be someone else's employees, which may result in a decrease in the construction workforce's average capability level. The answer in this phase is that governments should accept all the educational expenses incurred by the firms in proportion to their scales and financial structures as an input in improving building craftsmen performance, and in this way, as a tax deduction on money spent for training, because the return on investment from craft training occurs well within the first year (Thieblot 2002).
To work constantly in the same or similar activities in the construction sector, where tasks vary in a very wide spectrum, or, in other words, to have a complete experience in one trade is one of the key elements guaranteeing the work to be performed by a worker in a definite standard. If experienced building craftsmen are known to be available, supervisors do not have to explain details of how to perform the tasks to experienced workers.
Moreover, an estimator can foresee that the learning curve will not be significant, and productivity and quality of work will be better than those of a new or inexperienced worker. As the skill levels and experience of fellow workers increase, job-site safety and health concerns are likely to decline. This, in turn, may reduce workers' compensation costs and insurance costs in this industry. As a result, sustainability of the productivity level of construction workers now depends completely on specializing in a craft whatever are their positions as skilled or semi-skilled workers. On the other hand, experience and seniority concepts do not necessarily go hand in hand because the number of years that someone has been working in an industry may not be as relevant as the specific activities performed, and, thus, the quality and diversity of the work performed is far more important than the number of years in a particular position.
In the course of this sub chapter of factors that affecting the performance of building craftsmen, it show that performance of building craftsmen is being affected by many factors. There fore, is the time for the building construction management team to understand all factors affecting the performance of building craftsmen in the building construction industry and promptly be able to forecast and solve in advance some of the problems if not all, which may arise in future. This can be achieved through proper planning, supervision and scheduling of building construction activities.
There were different methods employed in data collection for the purpose of
This was a very essential question because it gives the way to understand the problem in detail. In the situation where the respondent has been working in building construction industry for a long period of time, obvious he might have been facing a lot of challenges; hence he will be giving accurate answers as compared to the one who was just engaged in the building construction industry for the first time.
This question helped to determine the current situation based on the performance of building craftsmen in the construction industry of Tanzania. Knowing the status of the performance of building craftsmen automatically simplified to recognise the extent to which performance of building craftsmen has been altered by those factors hindering the performance of building craftsmen in Tanzania, and hence suggesting best measures to reduce if not eliminating them.
This also was a very essential question in providing accurate answers for the study.
This was due to the fact that different building construction projects are faced by different challenges there fore by knowing the number of projects in which the respondent executed has given the researcher a clear picture of what the problems respondents has been executed through all projects he has been involved.
This question helped to measure the understanding knowledge of the building craftsmen based on the factors affecting their performance. This was helpful in suggesting on how to train building craftsmen so as to improve their performances and come out with high quality output.
This question was the heart of this study because it helped in identifying different factors which affects the performance of the building craftsmen in building construction industry of Tanzania.
Ranking major factors affecting the performance of building craftsmen helped to realise which factors were highly affecting the performance of building craftsmen and then scheduling appropriate strategies to eliminate those factors depending to the extent on how the factor affected building craftsmen performance.
This question challenged in determining the responsible organ for finding out the best practises towards eliminating those factors which reduces the performance of building craftsmen in Tanzania.
The question aimed at giving out the suggestion or opinions in reducing the effects of those factors which affects the performance of building craftsmen.
In this research data were collected from 15 construction companies which were undertaking building projects within Dar Es Salaam city. The data were collected in three weeks after the literature review had been carried out.
This composed of the filled information in the questionnaires that reflected the problem of the study under investigation. The process concentrated on the issues about identifying and raking the factors affecting the performance of building craftsmen.
Questionnaires were structured to different officials of building construction sector such as contractor's management team which includes site engineers, site foreman and technicians; also to different authorities' management officials such as TBA, ERB and AQRB officials.
Enquiries on various aspects regarding building craftsmen's performance apart from these structured questionnaires were made to a number of building craftsmen on various sites through personal interview. These Enquiries played a greater role in providing essential information of this study since they gave out accurate answers of what exactly affects the performance of building craftsmen; this is due to the fact that the answers were from the building craftsmen themselves.
Actual observations were organised and carried out in various building construction sites to provide extra information which had not been contemplated before.
The The data were obtained by the way of responses from different contractor's office, site agents and building craftsmen. The particular types of data were collected through structured questionnaires and the interviewing guidelines as in appendix A&B respectively.
To determine factors affecting the performance of building craftsmen respondents were required to identify major factors affecting the performance of building craftsmen. This tried to rank the identified factors which affect the performance of building craftsmen in the building construction industry. There were ten factors which hinder the performance of building craftsmen and they were ranked as shown in table 01.
A total number of 15 respondents responded to this question and below is the analysis of their answers in terms of percentages.
Taking the average between the factors which affect the performance of building craftsmen to a very large extent and those which affect the performance of building craftsmen to a large extent, it has been found that most respondents who were 43.33% ranked supervision and time as the major hindering factors to the performance of building craftsmen. Leadership factors took the second place with 40% of respondents followed by project complexity and motivation factors with 36.67% of respondents.
Material, tools and safety group stand in fourth position with 33.33% of respondents while quality and external groups were in fifth position with 20% of respondents.
Moreover it has been revealed that manpower group with 16.67% of respondents was a least group in affecting the performance of building craftsmen.
In terms of cost, time and quality of work done by building craftsmen on sites out of fifteen respondents 1 of respondent to questionnaires said that the performance of building craftsmen in Tanzania is very good, 3 said that it is good, 4 said it is satisfactory, 6 said it is poor and the remaining 1 of respondent said he don't know.
This implies that the performance of building craftsmen in construction sites is still very poor because majority of respondents who were 6 said performance of building craftsmen in terms of cost, time and quality is poor. To determine the responsible organ for finding out appropriate measures for reducing and eliminating factors affecting the performance of building craftsmen respondents were asked to select one or all of these organs; contractors, consultants, building craftsmen and government.
67% of respondents said all organs were responsible, while 20% and 13% said contractor and government respectively were responsible. No respondent said consultants and building craftsmen were responsible. These results indicate that all organs in building construction activities possesses a greater responsibility in improving the performance of building craftsmen in terms of cost, time and quality of output. For instance if the worker is well motivated by the contractor probably his performance will be high since he will be working with high morale, and if the government authorities such as AQRB make regular site inspection it will force the contractor to make sure that the building craftsmen works diligently to give out quality work at the required time.
100% of building craftsmen interviewed ranked material, tools and motivation group as the major factors affecting the performance of building craftsmen followed by time and supervision groups with 92% and 83% of respondents respectively. The least groups of factors affecting the performance of building craftsmen in ascending order were leadership and safety with 75% of respondents, project complexity group with 63% of respondents and manpower group with 50% of respondents. External group with 25% of respondents found to be not affecting the performance of building craftsmen to greater extent. In relation to findings from questionnaires by taking the average between interviews and questionnaires percentages it was revealed that time, motivation, materials and tools, supervision and leadership groups as the top five factors in affecting the performance of building craftsmen with the average percentages of respondents 68%, 68%, 67%, 63%, and 58% respectively. Safety, project complexity, manpower, quality and external were ranked as the least groups of factors in affecting the performance of building craftsmen with average percentages of respondents 54%, 50%, 33%, 27% and 23%.
100% of respondents said government and contractors were responsible for finding out appropriate measures to eliminate the factors affecting performance of building craftsmen. This implies that government through its professional boards such as AQRB, NCC, TBA and the contractor's management teams should play all the way in order to improve the performance of building craftsmen.
This tried to measure the current situation on the performance level of building craftsmen in the building construction sector of Tanzania.
In this research, actual site observations on factors affecting the performance of building craftsmen were made. The observations aimed at obtaining information regarding the common practice of construction activities particularly in Dar Es Salaam city.
Actual site observation done in different building construction sites revealed that the performance of building craftsmen in construction industry is poor and is mainly hindered by the factors here under;
It has been observed that material shortage on site was one among major problem which hinder the performance of building craftsmen in construction industry. Building craftsmen sometimes remained idle without job the reason behind the building craftsmen to stay idle without work was unavailability of building materials within the required time; this reduced the performance of building craftsmen since works were done in pieces which lead to non uniform quality of work. Unsuitability of material storage location was also the factor which affected the performance of building craftsmen; this caused time delay where materials were stored far away from the site and also double handling of materials in which materials were not properly arranged.
The unavailability of building materials on time was mainly caused by poor work plan, shortage of some materials from the suppliers, unavailability of storage facilities on sites and shortage of finance from the contractors.
Observation revealed that necessary plants and equipment such as excavators, cranes, and lifts were not used. Site of four to five floor were built without necessary plants such as cranes and lifts. Sand, cement and concrete were carried using head pans to upper floors, the quantity carried in such a way was very small and it took unnecessary too long to transport building materials in upper floor.
In the six sites observed the building craftsmen were doing their jobs without close supervision of site foremen. This was due to the fact that the site foremen were supervising more than one site at the same time, this reduced the performance of building craftsmen because if the building craftsmen got trouble in the drawing specifications or in any thing he has to wait until the site foremen come back; and also building craftsmen sometimes were cheating since there was no any one to check for the work.
Also due to poor leadership on sites, misunderstanding between building craftsmen occurred and reduced the performance of building craftsmen. This caused poor relationship among craftsmen hence poor quality of work produced.
From the site it has been observed that building craftsmen were working in seven days without taking holiday which made them tired and then produced poor quality work.
Not only that but it has also been observed that building craftsmen were doing the job more than eight hours which reduced their performance. The reason behind this factor is that during Saturday and Sunday building craftsmen were paid as a working days, but despite being motivated this is may reduce the performance of building craftsmen since as human beings their bodies are getting exhausted and need enough time to rest in order to perform well in terms of time, cost and quality of work.
In some sites it has been observed that building craftsmen were working within confined space which caused interference between different building craftsmen and even with labourers. This reduced the performance of building craftsmen since they didn't have enough space to perform their work conveniently.
It has been observed that Payment delay, Lack of financial motivation system, Lack of craftsmen recognition programs, Non-provision of transport means, Lack of places for eating and relaxation and Lack of training sessions affected the performance of building craftsmen because it made the building craftsmen to perform their jobs without employing extra effort and energy for the work.
In most of sites observed, building craftsmen were doing their job without taking care of safety measures. This problem was divided into two phases;
First, in some sites the safety gears were available but there was no safety official on construction site who cares if they were used or not, hence the building craftsmen took that opportunity and they didn't use such gears like helmets, safety belts, gloves, gumboot and others in their expense.
The second situation is that the building craftsmen were not using the safety gears because contractors didn't have those safety gears. This reduced the performance of building craftsmen since it leads to unnecessary accidents and sometimes death.
Both phases one and two of this factor can lead to low performance of building crafts men since they can cause accidents and eventually deaths on sites which may reduce workers morale to work.
Interviews conducted to at least three building craftsmen at each building construction site visited. For all interviewed building craftsmen, the common questions asked were based on the interviewing guideline attached in appendix B.
Respondents Number
This tried to rank the identified factors which affect the performance of building craftsmen in the building construction industry. Almost there were ten factors which hindered the performance of building craftsmen and they were ranked as indicated in figure 07.
This tried to measure the current situation on the performance level of building craftsmen in terms of time, cost and quality parameters in the building construction sector of Tanzania Findings 5 out of 24 interviewed building craftsmen said that the performance of building craftsmen in terms of time, cost and quality of output in Tanzania is very good, 2 said that it is good, 1 said it is satisfactory, 8 said it is poor and the remaining 7 of interviewed building craftsmen said they don't know. These results implies that the performance of building craftsmen is poor in Tanzania because majority of respondents who were 9 said the performance of building craftsmen is poor although some of them who were 5 tried to defend their performance by saying it is very good but in reality it is still poor and also most of building craftsmen don't know the status of their work as to whether it is quality or not. To determine the responsible organ for finding out appropriate measures for reducing and eliminating factors affecting the performance of building, the interviewed building craftsmen were asked to recognize responsible organ.
Generally from this study it has been observed that the building construction industry of Tanzania depends largely on the performance of building craftsmen. The factors materials, tools, supervision, leadership, quality, time, manpower, project complexity, external, motivation and safety are both influencing the performance of building craftsmen in building construction activities. Contractor's management team should understand those factors and implement them positively so as to acquire higher performance of the building craftsmen and eventually reducing time and cost overruns in various building construction projects.
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