What is design-build? How it works and its advantages

By Indeed Editorial Team

Published 19 October 2022

The Indeed Editorial Team comprises a diverse and talented team of writers, researchers and subject matter experts equipped with Indeed's data and insights to deliver useful tips to help guide your career journey.

Some construction innovations focus on modern elegance and aesthetics, while others concentrate on project efficiency and cost-effectiveness. Design-build falls in the latter category, representing a fundamental shift from the traditional design-bid-build model to a more systematic project contracting and handling method. Developing your knowledge of design-build will allow you to identify its features and understand how it differs from traditional design methods. This article considers 'What is design-build?' and explains its advantages, how to use it and how it contrasts with the traditional approach.

What is design-build?

So, 'What is design-build?'. It's a construction industry project delivery system where designers and builders collaborate on a project using a single contract throughout the project life cycle. The aim is to facilitate efficient project delivery through enhanced communication and collaboration of all professionals involved in building services design and construction projects. The model's ideal for simple tasks or technically complex projects that require a diverse team of experts.

The design-build model represents a progressive shift from the traditional method of handling construction projects where designers and builders work under separate contracts creating a less unified approach. Design-build allows a more unified workflow as all personnel work under a single entity and contract. A single contractor is responsible for the planning, design, construction and organisation to meet the client's requirements.

Related: How to become a design engineer (and design engineer skills)

The design-bid-build standard

The design-bid-build standard is the traditional approach for many building services design and construction projects. The first part of this approach is the project design, where the owner and the design team collaborate to outline the scope and design of the project. Then, the final design goes to the bidding phase, where contractors study the design, estimate cost and make appropriate bids. Finally, the building phase starts when they accept the offer. The general contractor, subcontractors and suppliers follow the specified design and timeline with little to no modification.

The whole system puts building owners at crossroads between designers and contractors. They manage two or more separate contracts and always serve as a liaison between both parties. This causes a delay in progress and sometimes puts designers against contractors.

Related: What is project design? (With elements, steps and tips)

A significant challenge of the design-bid-build model

A significant challenge in this approach is the lack of flexibility. Once a project design receives approval, modifications often involve going back to the drawing board. The design team, contractors and subcontractors may have different opinions on how best to effect any change. It often creates a decision-making bureaucracy that affects project time, budget and materials. This challenge stems from the fact that each sub-niche of the project is highly compartmentalised. Subcontractors such as plumbers, electricians and masons are primarily concerned about their specific roles. They're unaware of when expectation changes and how their role affects the whole project.

Another significant issue is the overburdening of project owners. They manage two separate contracts and deal with designers and contractors as distinct entities. Sometimes, clients don't know whether to refer the issue to the contractor or the designer, which can be confusing.

Related: What does a process design engineer do? (Duties explained)

How the design-build system differs from the traditional approach

With the design-build approach, there's a complete breakdown of the highly compartmentalised system of the traditional model. There's a unified workflow from conception to completion. Designers and builders work under a single contract to plan and execute all facets of a construction project. As such, there's only one point of responsibility and the whole team can quickly address changes. It's a major difference from the traditional design-bid-build system used in the building services design and construction industry.

Apart from this fundamental difference, the design-build model also ensures a culture of transparency. It makes sure everyone involved in the project is in agreement and understands their responsibilities. As a result, there's better collaboration and problem-solving becomes easier through effective communication.

How the design-build construction model works

It's best to view this model as consisting of three separate phases. Although these three phases are also part of the traditional model, the system is more fluid as the phases overlap. It's a critical distinguishing factor. For example, the design phase doesn't need full completion before the construction phase starts. Also, the same team manages the three phases from start to finish, creating a smooth working process.

The preconstruction phase

This phase is critical to the overall success of any design-build project. It starts from the conceptualisation and initial team selection by the project owner. After setting out the project's vision, needs and budget, clients vet design-build teams or firms based on experience and the set goals. The value engineering process the design-build model offers starts with this selection process. As both parties learn about each other, the issues of cost, quality and delivery schedule all take essential priority.

After completing all initial assessments and having a work team in place, the next step in this phase is the architectural design. Designers work with construction experts' input to create what fits the owners' requirements. The team then presents preliminary drawings, budget estimates and project schedules to the client. After doing all due diligence and establishing metrics of project deliverables, construction work can begin in earnest. There's no need for additional bids or contracts as designers and contractors make up the same team.

The construction phase

The construction phase can begin before the preconstruction phase is complete and the client approves the final design and budget. This is one of the peculiarities of the design-build model and leads to reduced cost and time. In addition, the communication levels established in the previous phase become heightened. All information passes through the same team and the client knows who to ask for updates on the project.

The post-construction phase

After completing the project, the design-build team provides appropriate personnel with detailed reports and training materials. Many of the activities in this phase also complement the design-build model. Since a single team was responsible for all aspects of the project, the documentation, turnover accounting and expansion plans became easier. Every project a design-build team executes is also crucial in building team rapport and learning from working creatively together. As part of this phase, the team also undergoes self-assessment to build on its expertise.

Related: What is design thinking? Stages, purposes and principles

What are the advantages of the design-build model?

The design-build model offers some advantages for construction project owners and work teams.

Cost-effectiveness

With the design-build model, the project team can more accurately establish the total budget from the onset. Early discussions and project analysis cover issues relating to cost and innovative ways to solve any impending problem. The entire project budget includes a fixed design fee and an implementation budget. Since the model emphasises a more holistic approach, designers and contractors engage actively from the start of the project. Project teams can more effectively manage an established budget without any significant change. The process saves additional costs caused by communication lapses and errors.

Related: Guide: cost-benefit analysis (uses, formulas and example)

Single point of responsibility

Instead of managing multiple contracts and working with separate entities for design and construction, project owners work with a single design-build contractor. This contractor is responsible for all phases of work on the project. The client communicates only with this contractor for all project updates and reviews. Also, when there's any default, the client knows who to address or where to seek legal remedies. It minimises risk for project owners. Irrespective of the number of subcontractors on the project, the client only has one point of contact and responsibility, which is the main design-build contractor.

Increased project speed

The organised scheduling and simplified project management enshrined in the design-build model mean the team can complete the entire project according to plan. The whole process, from planning to execution, follows a rapid pace that speeds up the project completion time. It gives the client and project team the benefit of making an early start on on-site work. It isn't necessary to complete the design before activities such as site clearing and foundation works can start.

Related: Project delivery methods (with tips)

Better teamwork and room for innovation

The design-build model allows various professionals to collaborate on a project from one phase to another. Instead of the siloed approach, where one expert handles a part of the project and hands it over to the next, the design-build model brings members together to propose the best course of action for various construction elements. As a result, there's reduced conflict between designers and contractors and more room for constructive ideas.

Higher quality of projects

The professionals often highly customise the final product of a design-build model. As designers and contractors form a single team, their collaborative efforts and creative problem-solving skills increase the quality of the project. The team is well-informed about all aspects of the project. Hence, they can pay more attention to specific details, streamline workflow and emphasise best practices.

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