REWORK IN RESIDENTIAL CONSTRUCTION IN CAMBODIA

By

San Visal

Abstract

Nowadays, Because of high demand of population, there are many construction projects is constructing in Cambodia. In addition, rework in one of the main unavoidable problem in construction project. Therefore, in order to understand of each impaction of each rework categories and propose recommendation to reduce those rework, this research was conducted. In order to achieve the objective of study this research was conducted by using questionnaire survey from 30 construction project which 12 of high rise concoction and 18 of low rise construction.

The research show that concrete strength under requirement that rarely occurred is high impact on time and cost in high rise construction and medium impact in low rise construction. Defective in rebar cutting, low quality of plastering and incorrect of erection form-work are the 3 rework categorize that is high frequency occurrence in high rise construction. Defective in rebar cutting is the rework categorize that is high frequency occurrence in low rise construction.

Moreover, it was found that both of rework happens in low rise and high rise construction cause by human resource ability is the highest one. It was followed by engineering & review, leadership & communications, material & equipment supply and construction planning & scheduling respectively.

             

Executive summary

Rationale of research

This research has been conducted to asses rework issues in Cambodian residential construction projects.

Objectives of study

The objectives of this study are:

To investigate the rework categories which impact time and cost in residential construction in Cambodia.

To identify the important factors direct caused rework in residential construction in Cambodia.

To propose recommendation to reduce rework in residential construction projects in Cambodia.

Methodology

The research methodology that supported by literature was developed in order to achieve the objectives of study. Methodology describes the method of data collection, data analysis and data interpretation. Finally, conclusions and recommendation were conducted to support this study.

Findings and conclusion

Rework was described as an inevitable event in construction project. Its occurrence has strong impact on project performance in term of time and cost. In addition, rework that was considered low, medium and high impact on time and cost depends on the type of rework and degree of its damage actually. On the other hand, some kind of rework that is low and medium impact could be considered as critical item if it happens quite often in construction project. Normally, change order, damage, error, failure, omission and deviation are the source that could cause rework occurring in construction project.

Moreover, different rework categories that occurred in construction project caused from different reasons that were categorized under 5 main groups human resource capability, engineering & reviews, construction planning & scheduling, material & equipment supply and leadership & communication.

Quantitative research design of 30 construction projects was applied in this research. Among these 30 construction project, there are 12 high rise construction and 18 low rise construction. The study is focusing on characteristic of each rework categories in term of frequency of occurrence, time & cost and direct causes during construction phase. Rework is an unavoidable event that occurred in construction project. In addition, it could be dissatisfied to participant in the project such as owner, sub-contractor and contractors.

In Cambodia, both of low rise and high rise construction, human resource capability is the highest factor that cause rework occurrence. It was follow by engineering & review, leadership & communications, material & equipment and construction planning & scheduling respectively. In addition, insufficient supervision is the main factor under human resource capability that cause rework occurrence in both low rise and high rise construction. Inadequate shop drawing details is the main factor under engineering & review that causes rework occurrence in low rise construction while inadequate shop drawing details and deviation from drawing are the 2 main factors that cause rework occurrence in high rise construction. Lack of communication between site supervisor and worker is main factor under leadership & communication that cause rework occurrence in low rise construction while lack of communication between contractor & inspector is the main factor that cause rework occurrence in high rise construction. Inadequate construction planning is the main factor under construction planning & scheduling that cause rework occurrence in both low rise and high rise construction. Low quality of equipment is main factor under material & equipment supply that cause rework occurrence in low rise construction while poor quality of material is the main factor that cause rework occurrence in high rise construction.

Recommendations

Rework occurrence in Cambodian construction projects is based on five main categories. Engineering and reviews, human resource capability, leadership & communication, material & equipment supply and construction planning & scheduling.

Therefore, the development model was produced in order to reduce rework in construction project.