Design-Build (DB) Concepts

Design–build (or design/build, and shortened D–B or D/B accordingly) is a project delivery system used in the construction industry. It is a method to deliver a project in which the design and construction services are contracted by a single organization known as the design–builder or design–build contractor.

The owner enters into a single contract with an organization that becomes responsible for both the design and the construction of the project. Design-build is also known as design/construct and single-source responsibility.design-build method successfully delivers lots of projects around the world, like office buildings, schools, stadiums, transportation and water infrastructure projects with premium results.

Design-Builder

a design-builder is the person or organization that provides design and construction services under a single design-build contract. This contract outlines the agreement between the Owner and the design-builder to provide architectural, engineering and concerning design services in addition to the labor, material, and associated construction services for the project, with concentrate on quality, cost, and speed of delivery.

Since there is only one contract, the design builder sees the project through the initial design concept to the completion of the construction, and assumes the responsibility of a single source. The design-builder is completely responsible and accountable for delivering all aspects of the project, including identifying any problems or matters, determining the underlying causes, and correcting them. They are also responsible for managing all contracts with other organizations, including subcontractors, material suppliers, and equipment vendors, and relieving the owner of this responsibility.

Design- Build vs Traditional Design–Bid–Build

Design-build is an alternative to design-bid-build. Under the latter approach, design and construction are split - separate entities, separate contracts, separate work. The owner must manage two separate contracts which all-too-often creates an adversarial relationship between the designer and the contractor. If something goes wrong or an unexpected circumstance requires changes, the designer and contractor blame one another for the cost overruns or schedule changes, often leading to dispute and delays which increase project cost.

In contrast to design–bid–build, design–build depends on a single point of responsibility contract and is used to reduce risks for the owner and to minimize the delivery schedule by overlapping the design phase and construction phase of a project. The owner manages only one contract with a single point of responsibility. The designer and contractor work together from the beginning, as a team, providing integrated project recommendations to match the Owner's schedule and budget. Any changes are addressed by the entire team, leading to collaborative problem-solving and innovation, not excuses or blame-shifting.

the Ministry of Manpower and Ministry of National Development of Singapore (1999) note that one of the primary reasons for low productivity in the construction industry is the lack of integration of activities across the project life cycle. Traditional design–tender–build approach has great potential for such lack of integration.

Design-build Company vs General Contractor

When a construction project is planned, a contractor is required. An owner can choose between a general contractor or a design-build organization, among other kinds of contractors.

A general contractor manages the construction portion of a project. It is provided with the design and then plans appropriately to complete the physical work of those plans according to specification. The general contractor will hold over subcontractors to perform carpentry, plumbing and other necessary specialist work. The general contractor does not participate with the owner in developing the design documentation.

A design-built company must carry out the same responsibilities and duties as a general contractor. However, the design-build company is also responsible for more than those duties. The design-build company oversees the entire project from start to finish, contributing of project from the initial vision of the construction project to the final function as well as the aesthetic appeal of the completed project.

Design-Build Process Steps

The Design-Build process has five main Stages:

1. Design-Build Team Selection Stage

The very first stage of design-build construction is the process of a project owner selecting their design-build team. Just like you would when hire any general contractor to perform a service, owners must review and consider potential design-build contractors based on their experience and ability to understand the needs and budget of the project owner.

2. Pre-Construction Planning Stage

Pre-construction planning typically begins as soon as the design-build team has been selected. During this stage, the design-build team will review and evaluate the construct ability of the entire project. The design-builder will need to analyze the owner’s goals, budget, potential challenges, and the overall concept of the project. It is also the time for asking as many questions as necessary to provide a complete impression of expectations for the finished project.

3. Architectural Design & Functionality Stage

Once a project’s framework has been clearly established, (project timeline, site, budget) the architectural design stage will implement. As many of these stages often overlap one another, an initial design approach may already have been started during pre-construction planning. Regardless, design-build team members will be working together to develop and advance the best possible project design to balance efficiency and budget for a successful project.

4. Construction Stage

If initial construction has not begun during the design stage, it will begin immediately following. When utilizing a design-build team, there is possible to be only a single point of contact between the owner and the construction team . When all parties are working towards the same goal, any unforeseen concerns or problems can be resolved quickly to allow deadlines to be met. The collaborative nature of design-build construction services provides value engineering by reducing unnecessary costs and keeps change orders to a minimum.

5. Post-Construction Stage

Once a project has been completed, the design-build team will provide an overview of the project in its entirety, including the project implementation, applicable operations & maintenance, and documented procedures throughout the project timeline. Any concerns of the owner may be addressed and finalization of completed work is established.

Design-Build Advantages

The Design–Build Institute of America (1994) lists top potential benefits from the design–build method as follows:

Singular responsibility. There is a single point of responsibility for quality, cost and schedule adherence, avoiding ‘buck passing’ and ‘finger pointing’.

Quality. The greater responsibility implicit in this method provides motivation for high-quality and proper performance.

Cost savings. The single entity with whom the owner contracts can work together as a team to evaluate alternative methods and materials efficiently and accurately.

Time savings. Design and construction can be overlapped, and bidding time after design is eliminated, thus offering the possibility of substantially reduced project duration.

Potential for reduced administrative burden. After the contract is agreed upon, the owner will have relatively little investment in coordinating and arbitrating between designer and contractor, since they are a single entity.

Early knowledge of firm costs. The single design–construction entity is responsible for both design and cost estimates at an early stage, thus allowing early establishment of financing and reduced exposure to cost escalation.

Risk management. Cost, schedule and quality can be clearly defined and appropriately balanced. The design–build organization will manage many of the risks that the owner might otherwise be responsible for.

Balanced award criteria. The owner can give credit in the award process for such considerations as design quality, functional efficiency and team experience, as well as lowest first cost.

Costly tendering. Owners must expect to pay for the efforts by design–build organizations to assemble their tenders. These efforts often include preliminary design work, necessary to determine prices.

Design-Build Disadvantages

To be fair, one should also recognize some disadvantages of the design–build method. These include the following.

Importance of the project brief. Without a clear statement defining the owner’s needs, the design–build organization cannot understand the required scope prior to contracting with the owner.

Difficulty of establishing a price for the work. It is difficult to establish a price for the work until the design is complete, which it is not when the design–build organization is selected.

Potential low quality. Oversight of the on-site construction activities is left to the owner. Because both designer and contractor are one organization, the designer cannot fairly represent the owner on site.

Less control over subcontractor and consultant selection. The owner is farther away, contractually, from the process of engaging subcontractors and sub consultants, whereas in the traditional design–tender–build process often the owner has the role of approving nominated subs.

Generally, less control by the owner.Over both project definition and execution than design– tender–build projects.