An investigation into design error and it impact on initial cost of construction project
1.1 BACKGROUND OF THE STUDY
When asked to define “design error,” not all disciplines in the construction process agree on a common definition. Depending on which discipline you address, the owner, the designer or the contractor, there will be a common understanding surrounded by varied conclusions, “a mistake.” From the basic definitions of “design” and “error” we conclude that a design error is a deviation from a drawing or specification, also including omissions and ambiguities. It is the seriousness of this error that must be considered to determine its consequences on the overall outcome of the project. One of the most important challenges facing management today is controlling the ball too frequent final cost and schedule overruns that effect the construction industry (Diekmann and Thrush, 1986). One of the major issues to control growth in project final costs and time is the reduction of design errors.
The owner, designer and contractor all have different interests in, or uses for the design of a facility. But what they do share is the commitment to complete the project safely and within a given budget and completion time. There are many initiatives being conducted to control the growth of final cost and schedule within the construction industry.
The major issue is “accuracy of the drawings,” or the number of design errors, omissions and ambiguities within the plans and specifications that affect the quality of the facility. Inadequacies in the plans and specifications are the major causes of changes to the contract So much emphasis is placed on the issue of time and final cost that quality takes a back seat .The quality of the project depends on the conformance of the objectives and requirements from the owner. An informative quality management technique will provide an agreement to procedures and definitions among the principle parties for the project. Since design errors have an impact on the outcome of the effectiveness of the contractor’s effort on the project it is essential that all parties determine what the definition of a design error should be.
1.2 STATEMENT OF THE PROBLEM
Design errors indicate the total design in-effectiveness of a project. Major design quality problems occur during construction when errors, omissions and ambiguities in plans and specifications become evident (Davis and Ledbetter, 1987). This statement directs that the inadequacies in the plans and specifications are the major causes of changes to the contract. There have been extreme examples of design errors such as numerous building collapses in Nigeria – projects that have wrought disaster after the construction are completed. These are examples of design errors that escaped the close scrutiny of all parties. One or two major errors that can be corrected with only initial cost considerations and little effect on the schedule can impact projects. The projects that really suffer are those with many small errors (design, rework or change of scope) which when finally added up causes major impacts on the final cost and schedule growth. Through Davis and Ledbetters research it was determined that “accuracy of the design documents” was the most critical of the criteria used in the initial evaluation of design effectiveness. This accuracy was further described as the concern for the frequency and impact of errors in the specifications and drawings. This is due to the fact that the drawings and specifications are the most “readily identifiable outputs of the design process.” It is even more important that the quality control of designs be addressed during the planning phase and closely monitored during the construction phase.
Design errors of a project have been an issue that has been misconstrued. The attitude towards design errors in the country can now be best described as tardy and unsatisfactory.
1.3 AIM AND OBJECTIVES OF THE STUDY
The main aim of the study is to investigate how design errors can affect the final cost of a project.
The specific objectives are:
- To determine what constitutes a design error.
- To examine the contributing factors to design errors in Nigeria.
- To examine how these factors can affect final cost of a project.
- To proffer solutions on how to minimise cost of construction projects in Nigeria.
- RESEARCH QUESTIONS
- What are design errors in construction projects?
- What makes or contributes to a design error?
- What are the factors that lead to design errors?
- What effect can design errors have on final cost and growth of a project?
- Who is responsible for design error?
1.5 HYPOTHESIS FORMULATION
- H0: Design error affect final cost of a building construction project.
H1: Design error does not affect final cost of a building construction project.
- H0: Design errors causescost overrun in a building construction project.
H1: Design errors does not causecost overrun in a building construction project.
- H0: Additional work causes additional cost in a building construction project due to design errors.
H1: Additional work does not cause additional cost in a building construction project due to design errors.
1.6 SIGNIFICANCE OF THE STUDY
This study gives a clear insight into the various ways in which contractors in the construction companies in Nigeria can maximise profits and reduce final cost through effective and efficient contract planning and management. The study also gives a clear insight into the various effects of design errors on the final cost of a project. The findings and recommendations of the researcher will help in building a strong and better project management guideline for contractors in Nigeria.
Also, the study of the investigation of the effect of design errors on the final cost of a project will provide results that will offer the following benefits:
- Establish the scope and methodology of design functions performed by Architectural firms for the benefit of the entire construction industry including prospective building clients.
- Assist designers in understanding the cost implication of design errors, so that they can make objective design decisions during the early phase of a project.
- Avail the designer with a tool for eradicating errors that are directly related to the designer that delay and or add cost to the project.
1.7 SCOPE OF STUDY
The study is on the investigation of the effect of design errors on the final cost of a project. It is narrowed down to building construction projects in Imo state of Nigeria.