**2. Impacted As-Planned Method**

SCL (Society of Construction Law) [16] defines the IAP method as introducing delay event sub-networks into a logic-linked baseline programme, and its recalculation using CPM (Critical Path Method) programming software to determine the prospective influence these events have on the anticipated contract completion dates revealed within the baseline programme. The numerous delays are structured as activities in IAP and added to the as-planned CPM schedule in chronological order, revealing how the project is being delayed by one delay at a time [17]. For delay analysis, this method simply employs a baseline (as-planned) schedule. The number of delayed days is equivalent the variance between the completion dates of the schedules before and after the impacts [11]. This method does not measure the effect of actual work performed but heavily relies on the validity of a baseline schedule [18]. The basic steps to implement IAP are as follows [14,19]:

1. Identify "un-impacted schedule" for delay analysis.

