An Exploratory Comparison of Cost and Schedule Performance Between Saudi Design–Bid–Build Projects and Published Integrated Project Delivery Cases

In Saudi Arabia, the sequential Design–Bid–Build (DBB) method dominates capital construction procurement. This exploratory study compares fifteen completed Saudi DBB projects from one public client portfolio with ten published international cases of Integrated Project Delivery (IPD). The two groups differ in procurement system, market conditions and reporting practice as well as in delivery method, so the comparison is a benchmark rather than a test of causal effect. The Saudi projects overran their budgets by an average of 27.5% and their schedules by 29.9%, while the IPD cases averaged +1.39% and −0.67%. Mann–Whitney U tests show that the two samples are statistically separated (p < 0.001; rank-biserial r = 1.00 and 0.97), a result unchanged when owner-initiated scope additions are excluded. Within this portfolio, the 80th-percentile overrun is approximately 37% for cost and 40% for schedule, rising to 41% and 44% if both must be met together; these are portfolio-specific estimates rather than general planning requirements. The size of the gap indicates that collaborative delivery elements warrant evaluation in the Saudi context.