Practice area 04
Schedule & Delay Risk Under Uncertainty
Delay is usually analysed after the fact and per project. The more useful question is which delivery structures absorb disruption better, and why.
The problem
Large construction projects have been documented as typically running about twenty percent longer than scheduled and up to eighty percent over budget under traditional non-collaborative delivery. Those figures describe ordinary conditions. Extreme uncertainty — supply chain collapse, labour unavailability, regulatory disruption — tests the delivery structure itself rather than the schedule.
Comparative evidence across delivery methods is hard to assemble because projects differ in scale, type and baseline. Normalising delay across a heterogeneous portfolio, using publicly verifiable disruption records, is what makes the comparison meaningful — and what allows the question to shift from 'was this delay excusable?' to 'which structures reduce exposure to delay in the first place?'
What governs this area
- Lean constructionPull planning, last planner, flow reliability.
- Delivery method comparisonIPD, CMAR, Design-Bid-Build, Design-Build.
- Uncertainty Schedule Delay IndexNormalised delay measurement across heterogeneous projects.
- Target Value DesignDesigning to a validated cost rather than estimating a design.
- Early engagementConstructor and trade input before design is fixed.
- Proactive procurementLong-lead identification and commitment under volatility.
The decisions it comes down to
- What is the schedule risk profile of each candidate delivery method for this project?
- Which long-lead items dominate exposure, and when must they be committed?
- How early must the constructor be engaged for that input to change the design?
- What does the contract say happens when disruption is neither party's fault?
- How is float owned, and who may consume it?
Basis
Academic. BC 6650 — Advanced Project Management; BC 6550 — Integrated Services, Georgia Institute of Technology.
Co-author of Schedule Delay in Construction Delivery Methods Under Extreme Uncertainty, published in the peer-reviewed proceedings of the 34th Annual Conference of the International Group for Lean Construction (Lean Theory track, pp. 655–667, DOI 10.24928/2026/0315, Scopus-indexed, open access). The study analysed seventeen non-residential projects across four delivery methods using a normalised Uncertainty Schedule Delay Index built from publicly verifiable multi-source documentation.
Writing in this area
Schedule Delay Risk: A Practitioner's Reading of the Comparative Evidence
Version 1.0