Progressive Design-Build – A Brief Overview
- Single design and construction package where the contractor performs both the design and construction in an integrated manner; but compared to a traditional, fixed-price DB: (1) PDB contractor may be engaged earlier and will negotiate the construction price later in the design process; and (2) the Owner, together with any interfacing contractors, is more involved in the design development
- Pre-construction: Design development; collaborative working groups; risk management; progressive build-up of Phase 2 schedule and cost on a GMP or FFP-basis when an acceptable level of design (typically 65–95%) is achieved
- Final design and construction: Final design and construction.
Progressive Design-Build – Advantages and What it Does Well
- Collaborative development of the design
- Owner has greater involvement than under a fixed price design-build and there is greater opportunity for incorporation of preference comments, not just compliance comments, but the Contractor still retains overall responsibility for design and construction
- In affordability-constrained projects, Owner and Contractor work together to identify value engineering opportunities
- Ability for the Contractor to work with the Owner to optimize and agree to the schedule concurrent with design development and before agreeing to the price – also enables flexibility to account for any delays in any Owner-retained responsibilities e.g., site access
- Similar to a fixed price design-build, offers opportunities for design innovation
- Similar to a CM/GC, offers opportunities to accelerate schedule through early works packages
- Compared to a fixed price design-build, negotiation of risk allocation and pricing when risks are better understood and design is further developed – reducing contingency pricing
- Compared to a fixed price design-build, negotiation of pricing closer to the time of construction – again reducing contingency pricing
Progressive Design-Build – Challenges and Lessons Learned
- Pricing is negotiated after Contractor selection
- Risk of an off ramp if not agreed and risk of a delay if an off-ramp is exercised
- This risk is heightened in a Progressive Design-Build compared to a CM/GC (although there are mitigations)
- Similar to CM/GC, the progressive design-build delivery method is resource intensive for the Owner.
- Until recently, traditionally utilized in the US for water/utility/vertical build projects – signs of increasing use in the transportation sector but it is a relatively immature market, with projects under implementation but not yet successfully completed
- As with a design-bid-build or CM/GC, the Contractor's focus is on the constructability of the designs and the construction means and methods, rather than lifecycle cost, long term maintainability and asset renewal – it is up to the Owner to work with its Contractor during design development to ensure that the designs and the construction means and methods meet their lifecycle cost and long-term O&M objectives
Explore Progressive Design-Build in more depth
Members will soon gain access to detailed Progressive Design-Build statutes, procurement examples, and case studies from current transportation projects.
Become a member