Impact of unplanned schedule compression on project cost

The implementation of unplanned schedule compression is common in the construction environment. When necessary, contractors would need to select methods that also minimize the cost impact on the project. Unfortunately, a limited knowledge exists for determining the methods to be employed in mitigating these potential negative outcomes of higher project costs. This study investigates the frequency of local contractors having experience with unplanned schedule compression, the methods of unplanned schedule compression percentage of usage, and their impact on project costs. The research was based on interviews and questionnaire surveys with building contractors in Penang. An analysis based on numerical scale was conducted on the responses to obtain the average values of impact on project cost. From the analysis, it was concluded that majority of the respondents have experienced unplanned schedule compression. The most frequently used compression methods are working overtime, employing additional workers and using additional work-shift. The least frequently used methods are set-up crew and special material clean-up crew. Detail project planning, doing it right the first time and construction sequencing have the least impact on increasing project cost. Most contractors select their methods based on familiarity instead of carefully considering the impact on project costs