Design-Build and EPC Delivery

Introduction
Design-Build (DB) and Engineering, Procurement and Construction (EPC) are integrated project delivery methods. In both, the owner hands responsibility for design and construction to one contracting entity. They appear often in the PMI Construction Professional (PMI-CP) exam. You must understand them to answer questions on contract lifecycle, risk allocation, procurement strategy and stakeholder management.

Why It Is Important
Choosing a delivery method is one of the most consequential decisions an owner makes. It shapes:
• who carries design risk
• how the schedule is compressed
• how costs are controlled
• how claims and disputes arise

DB and EPC have grown in popularity because they offer these benefits:
• Single point of responsibility: one contract covers design and construction. This eliminates the classic finger-pointing between designer and builder seen in Design-Bid-Build (DBB).
• Schedule acceleration: design and construction can overlap (fast-tracking). This shortens overall duration.
• Cost certainty: lump-sum or guaranteed maximum price (GMP) arrangements give owners earlier price commitment.
• Innovation: contractors can apply constructability knowledge early.
• Reduced owner administrative burden: the owner manages fewer interfaces.

For a construction project manager, knowing when these methods fit, and when they do not, is a core skill. The PMI-CP exam expects you to recommend appropriate delivery methods and manage their risks.

What It Is
Design-Build (DB): The owner contracts with a single entity, the design-builder, to provide both design and construction services.
• The design-builder may be a contractor-led team, a designer-led team, or a joint venture.
• The owner typically prepares a conceptual design or performance requirements. These are often called the Owner's Project Requirements (OPR) or bridging documents.
• The design-builder completes the design and builds the facility.

Engineering, Procurement and Construction (EPC): A variant of design-build common in industrial, energy, oil and gas, power, petrochemical and large infrastructure projects. The EPC contractor:
• handles detailed engineering
• procures all equipment and materials, including long-lead items such as turbines, compressors and transformers
• constructs the facility
• often commissions it, delivering a ready-to-operate plant

This is often called a turnkey arrangement. The owner simply turns the key to start operations. EPC contracts usually include performance guarantees, such as output capacity, efficiency or emissions limits. Liquidated damages apply for delay and for underperformance.

Key Variants to Know
• Progressive Design-Build (PDB): The design-builder is selected mainly on qualifications. The price is developed collaboratively as design progresses, often converting to a GMP or lump sum at an agreed point. Use it when the scope is not well defined.
• Bridging Design-Build: The owner hires a bridging consultant to develop the design to roughly 15 to 35 percent. DB proposers then compete on that basis.
• EPCM (Engineering, Procurement, Construction Management): The contractor provides engineering and procurement and manages construction as the owner's agent. Construction contracts are held by the owner, so the owner retains more risk.
• EPCC / EPCIC: EPC plus Commissioning, or plus Installation and Commissioning. Common in offshore work.
• Design-Build-Operate-Maintain (DBOM) and DBFOM: These extend the contractor's responsibility into operations, maintenance and sometimes financing, as in public-private partnerships.

How It Works: The Contract Lifecycle
1. Owner planning and requirements definition
• The owner defines business needs, functional and performance requirements, budget, schedule and risk tolerance.
• The project manager helps choose the delivery method, weighing scope definition, schedule urgency, owner capability, market conditions and regulatory constraints.
• For DB, the owner may produce bridging documents. For EPC, the owner produces a Front-End Engineering Design (FEED) package and an Employer's Requirements document.

2. Procurement and selection
Common selection methods are:
• one-step (direct proposal)
• two-step (RFQ shortlist followed by RFP)
• best value: a weighted evaluation of technical approach, qualifications, schedule and price
• qualifications-based selection, common in progressive DB

Stipends may be paid to unsuccessful shortlisted proposers to compensate for design effort. Alternative Technical Concepts (ATCs) may be allowed so that proposers can suggest innovations confidentially.

3. Contract formation
• Typical pricing models are lump sum (firm fixed price), GMP, or cost-plus converting to GMP.
• Standard forms include FIDIC Silver Book (EPC/Turnkey), FIDIC Yellow Book (Plant and Design-Build), DBIA documents, AIA A141 and ConsensusDocs 400 series, and NEC4 Option variants.
• Key clauses cover:
  - scope and Employer's Requirements
  - design responsibility and fitness-for-purpose obligations
  - performance guarantees and tests
  - liquidated damages for delay and performance
  - caps on liability
  - change and variation procedures
  - unforeseen site conditions
  - insurance
  - security (bonds, parent company guarantees)
  - dispute resolution (dispute boards, adjudication, arbitration)

4. Design development
• The design-builder or EPC contractor advances the design through schematic, design development and construction documents, or for EPC through basic and detailed engineering.
• The owner reviews submittals to confirm conformance with requirements. The owner should avoid taking over design responsibility, because excessive direction can shift risk back to the owner.

5. Procurement and construction
• Design and construction overlap through fast-tracking and phased packages.
• In EPC, the procurement of long-lead equipment, expediting, inspection at vendor shops and logistics form a major critical-path element.
• The project manager monitors progress with earned value, schedule analysis, quality audits and safety performance.

6. Commissioning, testing and handover
• Activities include mechanical completion, pre-commissioning, commissioning, performance testing, then taking-over or provisional acceptance.
• If performance guarantees are not met, performance liquidated damages or remedial obligations apply.

7. Defects liability, warranty and closeout
• A defects notification period follows, typically 12 to 24 months.
• Final acceptance, release of retention and bonds, and lessons learned complete the lifecycle.

Risk Allocation Comparison
• DBB: the owner warrants the design (the Spearin doctrine in US law), and the contractor builds to the plans.
• DB: the design-builder carries design risk. The owner still carries risk for its own requirements, for site conditions unless transferred, and for owner-caused changes.
• EPC lump-sum turnkey: maximum risk transfer to the contractor, often including ground conditions and fitness for purpose. Contractors add contingency, so bid prices are higher.
• EPCM: the contractor acts as agent, and the owner retains most cost and construction risk.

Advantages
• Single point of accountability.
• Faster delivery through overlap.
• Early cost certainty.
• Constructability and innovation.
• Fewer design-error claims against the owner.

Disadvantages
• The owner loses some control over design details.
• Higher risk premium in price.
• Requires well-defined performance requirements up front.
• Fewer bidders, because the method is resource-intensive.
• Quality may be compromised if the contractor optimizes for cost.
• Changes after contract award are expensive.
• Owner oversight capability is still required.

When to Choose DB or EPC
• Schedule is critical.
• The owner wants one contract and limited interface management.
• Requirements can be expressed in performance terms.
• The project is process- or equipment-driven (EPC).
• Lenders require price and completion certainty, as in project finance.
• The owner lacks in-house design management capacity.

Avoid lump-sum EPC when scope is highly uncertain. Consider progressive DB, EPCM or cost-reimbursable approaches instead.

Roles of the Construction Project Manager
• Advise on delivery method selection using a structured analysis.
• Develop clear Employer's or Owner's Requirements.
• Manage procurement and evaluation fairly and transparently.
• Oversee design reviews without assuming design liability.
• Manage change control rigorously.
• Monitor the contractor's schedule, cost, quality, safety and HSE compliance.
• Manage interfaces with operations, regulators and the community.
• Lead commissioning acceptance and handover.
• Administer claims and disputes per contract terms.

Exam Tips: Answering Questions on Design-Build and EPC Delivery

1. Identify the risk holder first. Many questions hinge on who bears design risk. In DB and EPC, the contractor is responsible for design errors. If the scenario describes a design flaw discovered during construction in a DB project, the design-builder generally absorbs the cost. The exception is when the flaw stems from owner-provided requirements or bridging documents that were mandated.

2. Watch for owner over-involvement. If an owner dictates detailed design solutions in a DB contract, it may assume liability for them. The correct answer usually involves the owner reviewing for conformance with requirements, not directing means and methods or detailed design.

3. Match the method to the scenario.
• Tight schedule plus a desire for a single point of responsibility points to DB or EPC.
• An industrial process plant with performance output guarantees points to EPC or turnkey.
• Poorly defined scope plus a need for collaboration points to progressive DB or CM at Risk.
• An owner who wants to retain control while using a contractor's procurement and engineering expertise points to EPCM.

4. Know the commercial terms. Lump sum, GMP, liquidated damages (delay versus performance), limitation of liability, fitness for purpose versus reasonable skill and care, stipends, ATCs, FEED, and mechanical completion versus taking-over.

5. Change management answers follow the contract. When a scenario involves a scope change or variation, the best answer is usually to follow the contract's change procedure. This means evaluating impact on cost, schedule and performance guarantees, documenting the change and obtaining approval. Do not proceed informally.

6. Choose proactive, collaborative actions. PMI favors early risk identification, clear requirements, structured communication and partnering. When unsure, pick the option that:
• analyzes before acting
• references contract documents
• engages stakeholders
• protects the owner's interests while preserving the relationship

7. Remember the trade-offs. Greater risk transfer means a higher price and less owner control. If a question asks why an EPC bid is higher than expected, think risk premium and contingency for transferred risks.

8. Commissioning and performance tests matter. In EPC, handover is not complete until performance tests are passed. If output falls short, the answer typically involves contractual remedies: remedial work, retesting, or performance liquidated damages. The owner should not simply reject the plant.

9. Distinguish similar methods.
• CM at Risk separates the designer from the builder. DB does not.
• EPCM is an agency or service arrangement. EPC is a risk-taking lump-sum arrangement.
• DBB is sequential. DB and EPC allow overlap.

10. Eliminate extreme answers. Options that terminate the contract immediately, ignore contractual notice requirements, or have the project manager unilaterally redesign are rarely correct.

Sample Question Approach
Scenario: An owner awarded a lump-sum EPC contract for a power plant. During detailed engineering, the contractor claims extra cost because the selected turbine needs a larger foundation than assumed. What should the project manager do?

Reasoning:
• Under EPC, the contractor is responsible for engineering and equipment selection.
• Unless the Employer's Requirements specified the foundation size or the turbine, this is contractor risk.
• The project manager should review the contract, the Employer's Requirements and the claim. They should respond according to the claims procedure, likely rejecting the claim if it is unsupported.

Key Takeaways
• DB and EPC consolidate design and construction under one entity, transferring design risk to the contractor.
• EPC adds procurement and often commissioning, delivers turnkey facilities, and features performance guarantees.
• Success depends on clear performance-based requirements, sound procurement, disciplined change control and robust owner oversight that does not cross into design direction.
• On the exam, focus on:
  - risk allocation
  - method suitability
  - following contract procedures
  - collaborative, proactive project management behavior