Progressive Design-Build (PDB): How It Works

Progressive design-build (PDB) is a form of design-build in which the owner selects a single design-build team primarily on qualifications, before design is developed, and then works with that team to progress the design and agree on a contract price in stages.

Typical ranges, not rules. Lump-sum design-build prices against bridging documents; PDB most often sets its GMP at 60 to 90 percent design, sometimes as early as 30 percent and often in packages. Sources: WCDA PDB Procurement Guide (2023), FHWA, CMAA.

In conventional, or best value, design-build, competing teams propose a design concept and a firm price, and the owner awards the contract on that combination. PDB reverses the order. The owner chooses the team first, then owner and team develop scope, schedule and budget together, and the price is committed only after enough design exists to support it. DBIA describes the absence of a contract price at award as “the biggest leap” owners have to take.

How it works

Qualifications-based selection. Teams compete on experience, key people and their plan for managing the project, sometimes with fees or rates as a minor factor. No construction price is part of the award.
Phase 1: design and preconstruction. Under a services agreement, the team advances the design, estimates cost on an open-book basis, and works through constructability, risk and schedule with the owner.
The price commitment. The team proposes a guaranteed maximum price or lump sum, most often when design is roughly 60 to 90 percent complete, sometimes as early as 30 percent, and frequently in packages.
The off-ramp. If owner and team cannot agree on price, the owner can end the relationship, keep the design, and finish the project another way.
Phase 2: final design and construction. Once the price is agreed, the same team completes the design and builds the project under a single contract.

PDB vs best value design-build

Selection. Best value scores technical proposals and price together; PDB selects mainly on qualifications.
Design. In best value, competing teams each develop concepts against the owner’s criteria; in PDB, owner and team develop one design together.
Price. Best value fixes a lump sum or GMP at award through competition; PDB negotiates it later, checked against independent estimates.
Owner involvement. Best value needs a clear, well-defined program up front; PDB needs an owner able to stay engaged through design and price negotiation.

When PDB fits

Scope is complex or uncertain, or will be shaped by discoveries during design.
Systems and technology must be integrated into the structure early, before the design is fixed.
The owner wants a direct hand in design decisions and has, or can hire, the capacity to manage an open-book negotiation.

What to watch

No price at award. Selecting a team without a price is uncomfortable for many public owners and their governing boards.
The off-ramp is rarely used. In a 2025 national survey of 25 state transportation agencies, 15 said they include off-ramps, but only two uses were reported. Leverage depends on independent cost estimates, not on the threat of walking away.
Owner capacity. Open-book pricing, independent estimates and owner’s advisors are what replace price competition, and they cost time and money.

The Parkonomics view

PDB matters most where the building has to hold technology. A garage’s PARCS, guidance, cameras and EV charging all need conduit, power and data designed into the slabs, which is hard to do when the technology vendor arrives after the structure is designed. Progressive delivery lets the systems and the structure be designed together. But it is a method for a progressive owner: the savings come from collaboration that the owner has to staff, measure and verify.

Further reading: Procurement Is Still Buying the Past While Parking Has Moved On

Sources: DBIA, Taking a Closer Look: Progressive Design-Build and Best Value Design-Build (2023); WCDA, Progressive Design-Build Procurement Guide (2023); NCHRP Synthesis 653 (2025).