Project Delivery Methods Explained: Design-Bid-Build vs. Design-Build

Navigating the complexities of construction projects often hinges on selecting the right project delivery method. At House of Eon Design, we recognize that the approach taken can significantly impact timelines, costs, and overall project success. Two of the most prevalent methods in the industry today are Design-Bid-Build and Design-Build. Each method is defined by its distinct advantages and challenges, making it crucial for project owners, architects, designers, and contractors to understand their differences. In this post, we will delve into these two delivery methods, shedding light on their unique processes and offering insights to help you choose the best fit for your next construction project.

Project Delivery and Procurement refers to obtaining services necessary for a construction project and typically defines the method by which the project is planned, managed, and completed. The project delivery method also determines how each party (owner, design team, construction team) works with one another throughout the design and construction phase.

The procurement process typically includes the following stages:

• Establishing the Project Scope, Schedule, and Budget

• Producing Design and Contract Drawings

• Soliciting Bids

• Reviewing Bids/Proposals

• Contractor Selection

• Contract Negotiation

• Construction Administration

• Payment and Closeout

The Project Delivery Method will determine how each stage above is conducted. The most common delivery methods in both residential and commercial projects are described below: 

Design-Bid-Build

The traditional, and most common, project delivery method in the industry is Design-Bid-Build (DBB). Description: the design team (architect, engineers, interior designers, consultants) and the construction team (general contractor and subcontractors) work directly for the owner under separate contracts. Design-Bid-Build follows a linear approach in which the owner first enters into a contract with the design team (architect & interior designer). During the design phase, the design team may enter into separate contracts with other engineers and specialty consultants as needed. During this phase, the design team works closely to develop, produce, and coordinate drawings, specifications, and other details that will ultimately become the construction documents. At each phase of design, the owner reviews and approves the design before moving on to the next phase. When the design is finalized and the construction documents are approved, the bidding and procurement phase begins. The bidding phase is the final step in the design process and involves sending out the construction documents to solicit contractors for bids.

On public projects (typically commercial) the lowest and best bid must be chosen (link to Commercial procurement post for a more detailed description of how bids for public projects are solicited, received, reviewed, and opened). For private projects, the owner is not obligated to choose the lowest and best bid and may choose, instead, to select a contractor they are familiar with or to interview a selection of contractors and decide which contractor they want to work with on their project. The contractor interview process typically involves a meeting between the owner (or owner’s representatives) and the contractor’s representatives. The contractor often presents examples of their work and describes their approach (project schedule and budget) to the current project. Once the contractor has been selected, the owner enters into a contract directly with their chosen contractor (separate from the owner-designer agreement) to begin the construction phase.

During the construction phase, the contractor is responsible for completing the project according to the construction documents and agreed-upon project budget and schedule. To oversee the construction phase, the contractor manages other subcontractors, orders materials, and coordinates with the design team to answer RFIs and submit any change order requests. Depending on the services laid out in their contract with the owner, the design team may also act as the owner’s representative during the construction phase by conducting site visits and construction progress meetings, processing pay applications/change orders/ RFIs submitted by the contractor and performing substantial and final completion punch lists.

The advantage of using the D-B-B method of procurement is that the owner has the opportunity to get the best price for their project, due to the competitive nature of the bidding process. The Design-Bid-Build method is a straightforward approach that provides a clear separation of responsibilities between the owner, the design team, and the construction team, eliminating conflicts of interest.

Design-Build

In contrast to the Design-Bid-Build method, where the client first hires an architect or designer to create detailed plans and then seeks bids from contractors to build according to those plans, Design-Build integrates these phases into one contract. In a Design-Build project delivery method, the responsibility for both the design and the construction phases of the project are conducted by a single entity under contract with the owner.

The Design Build team may be in the form of an already established Design Build firm or a separate architecture firm and the contracting team may join under one contract for a specific project. The “lead” may be either the architect/designer or the contractor, depending on the scope of work and type of project.

The key factors to consider in a Design-Build procurement method are:

1. Single Point of Responsibility: the owner contracts with both the design team and the contractor under a single contract, simplifying communication and responsibility.

2. Collaborative Approach: Design-build encourages collaboration between designers and builders from the very beginning of the project. This allows for cost estimates throughout the design process to be more accurate. The contractor will be better able to inform the owner of any cost implications, value engineering requirements, material availability, and project schedule impacts throughout the entire design process. This is in stark contrast to the D-B-B method mentioned above, in which the contractor may only see the drawings for the first time during the bidding process after the design phase is complete 

3. Faster Project Delivery: Because design and construction phases overlap and decisions can be made by both the designer and the contractor simultaneously, design-build projects often have shorter overall timelines compared to the traditional Design-Bid-Build method.

4. Potential for Project Cost Savings: The integrated approach can lead to cost efficiencies, as the design-builder can optimize designs based on their construction expertise and current market conditions.

Design-build procurement is particularly favored for projects where speed of delivery, cost control, and close collaboration between design and construction teams are critical. However, it may not be suitable for clients who prioritize a high level of custom design or who prefer a high degree of control over the design process.

Choosing the right project delivery method is a pivotal decision that can shape the outcome of your construction project. Both Design-Bid-Build and Design-Build methods offer unique advantages and cater to different project needs. Design-Bid-Build provides a clear separation of design and construction phases, potentially yielding competitive bids and a well-defined scope. On the other hand, Design-Build fosters collaboration and can expedite project timelines by integrating design and construction efforts.

At House of Eon Design, we believe that understanding these methods and their implications is key to making informed decisions that align with your project's goals. By weighing the pros and cons of each approach, you can pave the way for a successful and efficient construction journey.