Estimated duration comparison of construction activities by PERT Sample : Ordinary members of Home Builder Association

Abstract

The purpose of this research is to compare the estimation of construction activities duration by PERT method to reflect on reliability, and to prioritize the factors that affect the estimation of construction period. The sample consisted of planners from house construction companies which are ordinary members of the Home Builder Association. The research instruments are in-depth interviews and questionnaires. By simulating a residential construction project, have the planners estimate the duration of each activity using the PERT method and prioritize the factors. Data analysis includes 1) Descriptive Statistics 2) Likert Ranking Scale. The result demonstrates that (1) The minimum and maximum of schedule are 43.25 days apart, or approximately 1 month and 13 days. (2) A probability value of the schedule that the project will be completed Within the time limit the difference between the lowest and the highest was 99.99% (3) The activity that the planners estimated the most different duration were the plastering activities (4) The average of the highest priority factors of all activity Which can be arranged in descending order as follows : 1.Working skill 2.Weather 3.Site conditions 4.Materials 5.Transportation 6. Machinery 7. Accident.