American Journal of Civil Engineering and Architecture
ISSN (Print): 2328-398X ISSN (Online): 2328-3998 Website: Editor-in-chief: Mohammad Arif Kamal
Open Access
Journal Browser
American Journal of Civil Engineering and Architecture. 2018, 6(3), 105-118
DOI: 10.12691/ajcea-6-3-3
Open AccessArticle

Variation Mitigation Model to Enhance Construction Performance of Public Building Projects in Tanzania

Yusuph B. Mhando1, , Ramadhan S. Mlinga2 and Henry M. Alinaitwe3

1Department of Construction Economics and Management, Makerere University, Kampala, Uganda

2Department of Structural and Construction Engineering, University of Dar es Salaam, Dar es Salaam, Tanzania

3College of Engineering, Design, Art and Technology, Makerere University, Kampala, Uganda

Pub. Date: March 17, 2018

Cite this paper:
Yusuph B. Mhando, Ramadhan S. Mlinga and Henry M. Alinaitwe. Variation Mitigation Model to Enhance Construction Performance of Public Building Projects in Tanzania. American Journal of Civil Engineering and Architecture. 2018; 6(3):105-118. doi: 10.12691/ajcea-6-3-3


Detrimental variations are variations which negatively impact the project performance resulting into scenarios such as cost overruns, time overruns, project abandonment, rework, disruption and conflicts. These scenarios have led to non-fulfillment of project objectives. The objective of the study was to develop a mitigation model that helps to mitigate detrimental variations in public building projects in Tanzania. Specifically, the research question was how can detrimental variations be minimised in building projects? Literature review was carried out. Data were collected using questionnaire survey, group discussion and case studies. In total, 143 professionals (architects, engineers, quantity surveyors and procurement officers) participated in the survey. Statistical analyses such as Analysis of Variance (ANOVA), T-test analysis, Spearman’s rho correlation analysis and Principal Component Analysis (PCA) were used to analyse data and obtain relationships of variables. The analysis generated significant independent and dependent variables that formed the basis for the developed detrimental variation mitigation model. The model was validated through focus group discussion to test the model’s usefulness, clarity and applicability. Findings from case studies suggest that building projects suffered detrimental variations. The developed model when used significantly contributes to reduction of detrimental variations. Project parties should use the developed best practice model to enhance performance of construction projects.

building projects detrimental variations performance improvement mitigation model Tanzania

Creative CommonsThis work is licensed under a Creative Commons Attribution 4.0 International License. To view a copy of this license, visit


[1]  Memon, A. H., Rahman, I. A., & Hasan, M. F. A., “Significant Causes and Effects of Variation Orders in Construction Projects,” Research Journal of Applied Sciences, Engineering and Technology, 2(21), 4494-4502, 2014.
[2]  Ismail, A., Pourrostam, T., Soleymanzadeh, A., & Ghouyounchizad, M., “Factors Causing Variation Orders and their Effects in Roadway Construction Projects,” Research Journal of Applied Sciences, Engineering and Technology, 4(23), 4969-4972, 2012.
[3]  Ubani, E., Nwachukwu, C., & Nwokonkwo, O. “Variation Factors of Project Plans and their Contributions to Project Failure in Nigeria,” American Journal of Social and Management Sciences, 1(2), 141-149, 2010.
[4]  Mohemad, R., Hamdan, A. R., Othman, E. Z. A. & Noor, N. M. M., “Decision Support Systems (DSS) in Construction Tendering Processes,” International Journal of Computer Science Issues, 7(1), 35-45, 2010.
[5]  Park, Y., & Papadopoulou, T. C., “Causes of Cost Overruns in Transport Infrastructure Projects in Asia,” Built Environment Project and Asset Management, 2(2), 195-216, 2012.
[6]  Senaratne, S., & Sexton, M., “Managing Construction Project Change: A Knowledge Management Perspective,” Construction Management and Economics, 26(12), 1303-1311, 2008.
[7]  Motawa, I. A., “A Systematic Approach to Modelling Change Processes in Construction Projects,” The Australasian Journal of Construction Economics and Building, 5(1), 23-31, 2005.
[8]  Moghaddam, A. G., “Change Management and Change Process Model for the Iranian Construction Industry,” International Journal of Management Business Research, 2(2), 85- 94, 2012.
[9]  Kolawole, A. R., Kamau, K. P., & Munala, G., “Change Order Process Model for the Nigerian Construction Industry,” Journal of International Academic Research for Multidisciplinary, 4(1), 119-132, 2016.
[10]  Hao, Q., Shen, W., Neelamkavil, J., & Thomas, R., “Change Management in Construction Projects,” CIB W78 International Conference on Information Technology in Construction, Santiago, Chile. 2008.
[11]  Babatunde, S. O., “Quantitative Assessment of Cost and Time Implication of Susceptibility of Building Elements to Variation in Nigeria,” International Journal of Sustainable Construction Engineering and Technology, 4(2), 93-103, 2013.
[12]  Arain, F. M. & Pheng, L. S., “The Potential Effects of Variation Orders on Institutional Building Projects,” Facilities, 23(11/12), 496-510, 2005.
[13]  Love, P. E. D., Irani, Z., & Edwards, D. J., “A Rework Reduction Model for Construction Projects,” IEEE Transactions on Engineering Management, 51(4), 426-440, 2004.
[14]  Hwang, B., & Low, L. K. “Construction Project Change Management in Singapore: Status, Importance and Impact,” International Journal of Project Management, 30(2012), 817-826, 2011.
[15]  Arain, F. M., “Strategic Management of Variation Orders for Institutional Buildings: Leveraging on Information Technology,” Paper Presented at the PMI Global Congress Proceedings, Toronto, 1-17, 2005.
[16]  Mlinga, R. S., “Ethics in Public Procurement: A Missing Link in the Education and Training of Construction Industry Practitioners,” Paper presented at the Forum Proceedings, Construction Industry Forum, Organised by the National Construction Council of Tanzania, 12th -13th September, Dar es Salaam, National Construction Council, 1-19, 2008.
[17]  Subramani, T., Sruthi, P. S. & Kavitha, M., “Causes of Cost Overrun in Construction,” Journal of Engineering, 4(6), 1-7, 2014.
[18]  Enshasi, A., Mohamed, S., & Abushaban, S., “Factors affecting the Performance of Construction Projects in the Gaza Strip,” Journal of Civil Engineering and Management, 15(3), 269-280, 2009.
[19]  Aiyetan, A. O., & Smallwood, J. J., “Professionals’ Perceptions Regarding Factors Influencing Project Delivery Time,” Proceedings TG59 People in Construction, 12th -14th July, Port Elizabeth, South Africa, 225-234, 2009.
[20]  Rajeev, S., & Kothai, P. S., “Study on the Influence of Stakeholders in Construction Projects,” Journal of Construction Engineering and Project Management, 4(2), 8-11, 2014.
[21]  Emuze, F. A., & Smallwood, J. J., “Improving Project Delivery in South African Construction,” In: Proceedings of 27th Annual ARCOM Conference, September 5-7, Bristol, United Kingdom, 921-930, 2011.
[22]  Tadayon, M., Jaafar, M., & Nasri, E., “An Assessment of Risk Identification in Large Construction Projects in Iran,” Journal of Construction in Developing Countries, 1, 57-69, 2012.
[23]  Ammar, M. A., Elsamdomy, A. A., & Rabie, A. A., “Risk Allocation and Mitigation in the Egyptian Barrage Projects,” Proceedings of the 13th International Conference on Structural and Geotechnical Engineering, December 27-29, Ain Shams University, Cairo, 180-190, 2009.
[24]  Priyantha, T. H. S., Karunasena, G., & Rodrigo, V. A. K., “Causes, Nature and Effects of Variations in Highways,” Journal of Built Environment - Sri Lanka, 09-10(01-02), 14-20, 2011.
[25]  Ibbs, W. “Construction Change: Likelihood, Severity, and Impact on Productivity,” Journal of Legal Affairs and Dispute Resolution in Engineering and Construction, 4(3), 67-73, 2012.
[26]  Simpeh, E. K., Ndihokubwayo, R., & Love, P. E. D., “Field Diagnosis of Causes and Effects of Rework in Higher Education Residential Facilities,” Journal of Construction, 4(1), 1-11, 2011.
[27]  Alinaitwe, H. M., Improvement of Labour Performance and Productivity in Uganda’s Building Industry, Ph.D Thesis, Sweden: Lund University, 2008.
[28]  Taggart, M., Koskela, L., & Rook, J., “The Role of the Supply Chain in the Elimination and Reduction of Construction Rework and Defects: An Action Research Approach,” Construction Management and Economics, 32(7-8), 829-842, 2014.
[29]  Jelodar, M. B., Yiu, T. W., & Wilkinson, S., “Systematic Representation of Relationship Quality in Conflict and Dispute for Construction Projects,” Construction Economics and Building, 15(1), 89-103, 2015.
[30]  Chikere, C. C., & Nwoka, J., “The Systems Theory of Management in Modern Day Organizations: A Study of Aldgate Congress Resort Limited Port Harcourt,” International Journal of Scientific and Research Publications, 5(9), 1-7, 2015.
[31]  Kombo, D. K., & Tromp, D. L. A., Proposals and Thesis Writing: An introduction, Nairobi: Pauline’s Publications Africa, 2006.
[32]  Palinkas, L. A., Horwitz, S. M., Green C. A., Wisdom, J. P., Duan, N., & Hoagwood, K., “Purposeful Sampling for Qualitative Data Collection and Analysis in Mixed Method Implementation Research,” Adm Policy Ment Health, 42(5), 533-44, 2015.
[33]  Tongco, D. C., “Purposive Sampling as a Tool for Informant Selection,” A Journal of Plants, People and Applied Research, 5, 147-158, 2007.
[34]  Rahi, S., “Research Design and Methods: A Systematic Review of Research Paradigms, Sampling Issues and Instruments Development,” International Journal of Economics and Management Sciences, 6(2), 1-5, 2017.
[35]  Mohammad N., Ani, A. I. C., Rakmat, R. A. O. K., & Yusof, M. A., “Investigation on the Causes of Variation Orders in the Construction of Building Project: A Study in the State of Selangor, Malaysia,” Journal of Building Performance, 1(1), 73-82, 2010.
[36]  Fellows, R. & Liu, A., Research Methods for Construction, Chichester: Wiley Blackwell Publishing Ltd, 3th edition, 2008.
[37]  Wong, L. P., “Focus Group Discussion: A Tool for Health and Medical Research,” Journal of Medical Education, 49(3), 256-261, 2008.
[38]  Stewart, D. W., Shamdasani, P. N., & Rook, D. W., Focus Groups: Theory and Practice, Newbury Park: Sage Publications, 2nd edition, 2007.
[39]  Spillane, J., & Oyedele, L., “Strategies for Effective Management of Health and Safety in Confined Site Construction,” Australasian Journal of Construction Economics and Building, 13(4), 50-64, 2013.
[40]  Cohen, L., Manion, L., & Morrison, K., Research Methods in Education, New York: Routledge, 6th edition, 2007.
[41]  Breen, R. L., “A Practical Guide to Focus-Group Research,” Journal of Geography in Higher Education, 30(3), 463-475, 2006.
[42]  Yin, R. K., Case Study Research: Design and Methods, London: SAGE Publications, 4th edition, 2009.
[43]  Suryanarayana, T. M. V., & Mistry, P. B., “Principal Component Regression for Crop Yield Estimation,” Springer Briefs in Applied Sciences and Technology, 17-25, 2016.
[44]  Manerikar, V., & Manerikar, S., “Cronbach’s alpha,” A Peer Reviewed Research Journal - aWEshkar, XIX (1), 117-119, 2015.
[45]  Hair, J. F., Anderson, R. E., Tatham, R. L., & Black, W.C., Multivariate Data Analysis, Upper Saddle, New Jersey: Prentice-Hall Inc, 7th edition, 2010.
[46]  Dmaidi, N., Dwaikat, M., & Shweikh, I., “Construction Contracting Management Obstacles in Palestine,” International Journal of Construction Engineering and Management, 2(1), 15-22, 2013.