Design-Build
From Wikipedia, the free encyclopedia
Design/Build (D/B) is a construction project delivery system used to reduce the project delivery time by overlapping the design phase and construction phase of a project.
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[edit] History
The Design/Build delivery system is based upon the original Master Builder concept used to build most pre-modern projects. Under the Master Builder approach a central figure or organization held total project accountability. From inception to completion through performance, the Master Builder was the key organizational figure. The Design/Build system is a return to the fundamentals of the Master Builder ideals.
[edit] Overview of Process
Design/Build focuses on interweaving the design, permit, and construction schedules in order to capture the time lost in a traditional Design-Bid-Build environment. This does not shorten the time it takes to complete the individual tasks of creating drawings, acquiring building permits, or actually constructing the building. Instead, a quality Design/Build firm will bring together design and construction professionals in a collaborative context to complete these tasks at the same time. This is akin to the technological concept of Parallel Computing. Using this mechanism, Design-Build represents a risk management strategy that places a premium on delivering the project sooner with less of a focus on delivering the project at a lower construction cost.
Typically one organization is responsible for both design and construction of the project. If this organization is a contractor, the process is known as "Contractor-Led Design/Build". If the organization is a design firm, the process is known as "Design-Led Design/Build". In either case, the organization employed by the owner rarely handles both aspects of Design and Construction in-house. In fact, the organization often subcontracts with on-site personnel (if Design-Led) as well as architects, designers (if Contractor-Led), planners etc.
Owners should consider the benefits of each form of Design/Build in determining what sort of D/B firm to engage for a project. As a general rule, the more complex a project becomes, the more valuable the Design-Led model becomes.
[edit] Typical Process
1. Client has a need for a new building or renovations to an existing building.
2. Client (or his agent/advisor) prepares a list of requirements for the new space.
3. Client engages a Design/Build firm to develop a concept and perhaps a Guaranteed Maximum Price and passes the requirements on to them.
4. The D/B firm prepares design, time, and cost proposals, and submits these proposals to the Client.
5. Proposals accepted: contract
6. Contractor designs, carries out and completes works employing resources (in-house staff or sub-contractors) for all aspects.
[edit] Potential Problems
Estimating for a Design/Build project is sometimes difficult because plans are often preliminary and can change over the course of the project. Because of this difficulty in estimating, contracts must be written in a way that provides for unexpected situations without penalizing either the Design/Builder or the owner. Several trade organizations (like the Design-Build Institute of America) provide standardized form contracts for Design/Builders to use but it is not unusual for the Design/Builder to have its own contractual documents prepared or even keep attorneys on staff to handle contract drafting according to the negotiated terms. This effectively requires the owner to rely a great deal on the integrity, accumen, and competence of the Design/Builder. As the certainty of estimates decreases, the opinion of the construction professionals of the D/B firm must be trustworthy, accurate, and reasonably verifiable to reduce risk.
[edit] Benefits
It is important to note that the Design/Build method, while not focussed on saving the owner construction costs nonetheless often saves the owner money on the overall project. The combined effects of carrying a construction loan (which typically carries a higher interest rate than permanent financing) and an earlier useful on-line date usually yields considerable overall profitability to the project.
The compression of time is only one important aspect of the implementation of this system. Other attributes include:
- increased accountabilty by the service provider,
- single source project delivery, and
- a value based project feedback system
[edit] Accountability
Rather than a parcelized level of responsibility of the classic Design-Bid-Build, Design/Build provides an integrated solution for the owner or client. This provides refuge from the finger-pointing that has become (unfortunately) commonplace in modern construction projects and allows the owner to look to one entity with questions or concerns.
[edit] Single Source
Instead of having several contractors and consultants to deal with, an owner has just one contact for the project. Design revisions, project feedback, budgeting, permitting, construction issues, and billing can all be routed through the Design/Build firm. This single point of contact allows maximum flexibility for the owner to insist on a particular course of action without having to readjust contracts with perhaps a dozen contractors. A quality Design/Builder will leverage that flexibility for the owner's benefit by continually refining the construction program to maximize the owner's value at the completion of the project.
[edit] Value Based Project Feedback
Typically, in order for a contractor to bid on a project, very specific details relating to the methods and materials must be given to avoid any ambiguity and to make an "apples to apples" comparison of bids. In a Design/Build context, the owner, the owner's other consultants, and the Design/Builder can work together to determine what methods and materials will maximize the owner's value. In instances where marginally more expensive materials, designs, or construction methods might yield a higher return on investment for the owner than those of lower cost, the owner is free to adjust the project's program without having to re-bid the project themself.
