Assessing the effect of design errors on the initial project duration estimate.

Abstract

Design errors can adversely influence project performance and can contribute to failures, accidents, and loss of life. Although there has been a considerable amount of research that has examined design error causation, little is known about design error costs. This research project investigated the effects of design errors on the initial project duration estimate in Kampala. The objectives of the study were to give an understanding of what constitutes a design error, to establish the main causes of design errors, to find out how often project delays are caused by design errors, and to find out possible solutions to minimize design errors in designing construction structures. The researcher managed to reach out to 20 firms and for each firm, 4 questionnaires were distributed so that variety of data is obtained from architects, civil engineers, managers and also quantity surveyors. So, that made a total of 80 questionnaires sent out. On return,57 questionnaires were collected which makes a percentage of 71.3%, which is a good response rate. Only 5 interviews were conducted so that the researcher could obtain deep information about the topic and the analysis of data was done using Microsoft Excel. It was found out that design errors were perceived to be Errors done in designing(drafting) of drawings and calculations that make a project expensive during the later stages of construction or errors or omissions in the plans and specifications which must be corrected in order to provide a facility which is complete and useable, and which achieves the design intent. Responsibility for design errors was heavily attributed to designers and it was also discovered that 14.67% of project delays are usually caused by design errors among the other causes of delays. Among the causes of design errors were; lack of proper field investigation, owner changing the design criteria during the design process, lack of coordination among the design team, inexperience of the design professionals, mis-coordination between the designer and the consultants, client not communicating exactly what is required, budget and time pressure on the designer, ineffective utilisation of cad, complex and unusual projects, calculation errors, un clear communication of the design intent, and human error. Solutions included raising design fees and hiring more competent designers, emphasize the importance of proper field investigation, use cad software more efficiently, communicate goals clearly and concisely by the client, and many more others.