Other Delivery Methods
The design-build delivery method is a shift from the more traditional design-bid-build delivery of construction contracts. Successful design-build projects offer an owner many benefits that add value to a project. These advantages include:
Single Point of Responsibility
A design-build contract combines design and construction quality, cost, and schedule into a single point of responsibility. Design-build contracts foster partnering between team members, which in turn adds value to a project. This single point of responsibility also helps the design-build team avoid potential adversarial relationships that could arise under traditional, design-bid-build contracts.
Improved Project Quality
Using the design-build delivery, the architect and contractor coordinate as a team, leaving an owner free to focus on the project’s scope and general decision making. This leads to a higher quality project that better suits the owner’s needs in the following ways:
The design-build team works together to produce a complete set of construction documents. By contrast, with a design-bid-build delivery, the owner is responsible for providing complete documents to the contractor.
Constructability can be reviewed throughout the design process by all members of the design-build team. This leads to effective value engineering ideas created by the architect, contractor and engineer working together to maximize design and functionality while maintaining budgetary and schedule concerns.
Earlier knowledge of Guaranteed costs
The design-build delivery system allows the contractor to establish a guaranteed cost early on in the design phase. This allows the owner to make changes, request additional value engineering, or add scope to a project before the substantial design is complete.
Value engineering and constructability review are enhanced and utilized continuously throughout the project duration. The early involvement of the design-build team is essential in maximizing the full potential of the design-build delivery system. Decisions that can be made during the programming, concept and design phases will impact the schedule and costs of the project more than any other phase of construction.
With a design-build project, design and construction for a project can easily overlap, allowing for fast track construction. The owner benefits from this shortened timeframe because construction costs can be reduced and the new building will be available for use sooner.
Improved Risk Management- Because the design-build team has the responsibility for developing drawings and specifications as well as constructing a fully-functioning facility, change orders for errors and omissions are virtually eliminated. Each stake holder on the design-build team is responsible for the risks they are best positioned to manage.
The overall project performance is enhanced through the partnering that is unique to the design-build delivery method. This alleviates the potential for the adversarial conflicts realized when each entity is looking after their own best interests.
Selecting the design-build team should occur earlier in the construction process, offering the greatest potential to save both time and resources. However, the exact timing depends on the project complexity and the owner's capabilities. A design-build team can be selected through a competitive bid process or by negotiation.
Competitive Selection- Under this arrangement, the owner must provide a Request for Proposal (RFP) that will clearly and fairly identify requirements for both the building and the design-build team. The RFP should include all programming, project criteria and definitions to allow a meaningful and fair competition. The most challenging aspect of preparing an RFP is creating a statement of facility requirements that is comprehensive enough to assure compliance by the design-build teams, but avoids overly restrictive requirements that inhibit creativity.
Negotiated Selection- Selecting a design-build team through a negotiation process allows the owner to avoid creating an RFP, saving both time and cost. This gives the design-build team input during the critical planning and conceptual stage.
Regardless of the selection process utilized, owners should evaluate on the following criteria:
Unlike a design-bid-build delivery, a design-build delivery can easily be broken into two separate contracts. This allows the owner to take a second look at the project before committing to complete the project. The structure for a split contract may look something like the following:
Contract One: The design-build team is contracted to complete the project design in sufficient enough detail to fix the price of the project.
Contract Two: The design-build team is contracted to complete the design documents and the construction work.
An additional consideration when drafting a design-build contract is balanced risk. Design-build projects inherently impose additional risk and responsibility upon the contractor. Contract language should not attempt to pass along risk rightfully shouldered by the owner. Examples of such unbalanced risk transfers include environmental issues, concealed or undiscovered conditions, differing site conditions and third party delays (such as permitting delays beyond the contractor’s control).