Published on 09th May 2023
Design-bid-build delivery method is a traditional project delivery method used in the construction industry. Also known as the DBB method, the process involves contracting separate entities for the design phase and construction process.
In this method, the owner first hires an architect or civil engineer to design the project and then invites bids from general contractors. Sometimes, the owner may hire a separate construction management entity to oversee the project.
The DBB construction method has been used for decades and is one of the most commonly used project delivery methods in the construction industry.
This blog explains everything you need to know about the Design Bid Build project delivery method.
Design Bid Build delivery method or DBB delivery method is one of the most widely used project delivery methods in the construction industry. In the design bid build method, the project owners sign contracts individually with designers and contractors. There is no contractual bond between designers and contractors, except the channels for coordination and communication.
It provides a clear separation between the design and construction phases. It also allows the owner to control the design process and ensures competitive pricing for the construction work. However, it also has some drawbacks, including a longer overall project timeline and potential disputes between the parties involved.
This system is a common method used and is found to suit clients of all types, particularly government institutions for public projects. Due to the feature of linear progression, this system provides better management for the client, but it gives little consideration to the designing, information communication, and construction delivery.
Design phase: The owner engages a design consultant to prepare the design of the project, including construction drawings, and specifications. The Design Consultant may also provide additional services including environmental investigation, permitting, right‐of‐way purchase documents, stakeholder management, and submissions for project funding.
Bid phase: Once the design phase is completed, the tender is floated. The general contractors bid on the design bid build projects based on the completed design plans and specifications. Thereafter, the owner selects the lowest responsible bidder to build the project.
Sometimes, the project owner considers a hybrid of price and technical merit for selecting the right contractor. The selected general Contractor and the owners then sign the contract documents. The main contractor may then hire various subcontractors for specific parts of the project.
Build phase: The awarded general contractor is responsible for constructing the project in accordance with the contract documents. At this stage, the design consultant typically maintains limited oversight of the work and responds to questions about the design on behalf of the owner.
If a construction manager or project manager is not involved in the process, the Design Consultant may also assist the owner in administering the construction contract, including the determination of project progress, for validation of interim payments made to the general contractor.
MPC or Multiple Prime Contracting is an important aspect of a DBB project. As per MPC, the owner holds separate contracts with various contractors, such as structural contractor, mechanical contractor, and electrical contractor. In this system, the owner, or its construction manager, manages the overall schedule and budget.
The project manager (PM) or construction manager (CM) is responsible for the following tasks in a DBB construction project.
The DBB delivery method has been the standard project delivery method for many years. This method gives the owner reliable price information for the project before construction starts. With proper design oversight and budgeting of the total project, costs are somewhat predictable for the owner once the bids are received. However, there are some inherent risks associated with the method which are described below.
The main difference between Design-Bid-Build and Design-Build is the type of contract involved. While in the DBB construction method, the owner signs different contracts with different entities for design and construction, in the DB construction method, a single contract, similar to an EPC contract, governs the entire project.
| Criteria | Design-Bid-Build | Design-Build |
| Contract structure | Three separate contracts govern three different phases of the project - design, construction, and project management. | A single contract governs the entire project right from design to construction and management. |
| Project control | The project owner has more control over each phase of the project. | The project developing entity has more control over the project as it handles both design and construction. |
| Cost control | Owner controls the cost of the project by directly getting involved. Further, the owner can save costs by choosing the lowest bid for design and construction. | The contractor can maximize the construction profit margin by identifying various cost-saving opportunities throughout the project. |
| Communication | issues may arise between the stakeholders of each phase as the owner, designer, and contractor are responsible for different phases of the project. | Chances of better communication and coordination among the various teams as all of them work under a single contractor. |
| Approach | The construction takes place in a linear process where one phase can not start until the previous phase is finished. | A collaborative process by every team and work can start in advance as every team is aware of what is going on in the project. |
DBB process at a glance:
