The right route depends on how much control you want over the design and how much responsibility you want to hand over. Traditional contracting separates design from construction and gives you close control of every drawing. Design-and-build puts design and construction under one contract and one point of responsibility, often with a faster programme.
Neither route is better in every case. Each moves risk, cost and control to different places. This guide explains how each works, where each is strong and where each tends to go wrong, so you can choose with clear eyes.
What is traditional contracting?
Traditional contracting is sometimes called design-bid-build. It runs in sequence:
- The client appoints an architect and engineers.
- The design team completes the drawings and specifications.
- A Bill of Quantities is prepared and the project is tendered.
- The client appoints the contractor, usually on price.
- The contractor builds to the client's design, with the design team inspecting.
The client holds two sets of contracts: one with the designers, one with the contractor. In international practice this is the model behind the FIDIC Red Book, where the employer provides the design.
What is design-and-build?
In design-and-build, the client appoints one organisation to design and construct the project under a single contract. The client provides a brief, often called the employer's requirements, and the contractor develops the design and builds it. In international practice this is the model behind the FIDIC Yellow Book.
Turnkey delivery is a fuller form of design-and-build, where the contractor hands over a finished, ready-to-use building.
How do the two routes compare?
| Factor | Traditional contracting | Design-and-build |
|---|---|---|
| Responsibility | Split between designer and contractor | One party for design and construction |
| Design control | High: the client directs the design team | Lower: the client sets requirements, the contractor designs |
| Programme | Longer, because design finishes before tender | Shorter, because design and construction can overlap |
| Cost certainty at contract | Good, if the design is complete and fully measured | Good on the agreed scope, if the requirements are clear |
| Cost of change | Variations valued against the priced BOQ | Changes to the requirements can be costly once agreed |
| Buildability | Depends on how well designers understand construction | Built in, because the builder designs |
| Disputes | Risk of disputes over design versus workmanship | Fewer interface disputes, but quality depends on the brief |
| Client effort | Manages several appointments | Manages one main relationship |
When is traditional contracting the better choice?
Traditional contracting suits projects where design control matters more than speed:
- Design-led buildings, where architecture and finishes define the value of the project.
- Clients with in-house expertise who want to direct the designers closely.
- Public or regulated procurement, where competitive tendering on a complete design is required.
- Projects with time to plan, where a fully finished design and BOQ reduce price risk at tender.
The weak points are time and responsibility. The design must be finished before the contractor is appointed. When a problem appears on site, the designer and the contractor may each say it belongs to the other, and the client sits in the middle.
When is design-and-build the better choice?
Design-and-build suits projects where clear responsibility and a faster programme matter most:
- Clients without a technical team who want one accountable partner.
- Commercial and industrial buildings, where function, cost and opening date matter more than bespoke design.
- Projects with heavy engineering content, such as steel structures and MEP systems, where buildability drives cost.
- Tight programmes, where starting early works on site before every detail is drawn can save significant time.
The weak points are control and the brief. The contractor makes design decisions within your requirements. If those requirements are vague, the contractor is entitled to meet them in the most economical way, which may not be what you imagined. A design-and-build project is only as good as its brief.
What are the common mistakes with each route?
Traditional contracting:
- Tendering an incomplete design, which leads to variations and claims.
- Choosing the lowest bid without checking the BOQ rates line by line.
- No clear process for resolving design questions on site.
Design-and-build:
- A short, vague brief that leaves quality undefined.
- Changing requirements after the contract is signed.
- No independent review of the contractor's design and workmanship.
How do you decide?
Ask four questions:
- How fixed is your design? If it is already complete, traditional contracting uses it fully. If you have a brief and a budget, design-and-build lets the builder develop it.
- How much control do you want? Close control of every detail favours traditional. Control of outcomes favours design-and-build.
- Who do you want to call when something goes wrong? If the answer is "one party", design-and-build fits.
- How fast do you need to finish? Overlapping design and construction is the main time advantage of design-and-build.
Some clients use a hybrid. They appoint an architect for the concept, then pass the design to a design-and-build contractor to complete and build.
Where does Laurent fit?
Laurent's positioning, "One Partner. Complete Project Delivery.", describes the design-and-build model: one team taking ownership from design and engineering to execution and handover. For SR Padel Egypt in Cairo, Laurent designed and built the padel courts, covering the steel structure, engineering and installation.
That does not make it right for every project. If you already have a complete design from your own architect, traditional contracting may serve you better, and that is worth discussing openly before you choose. You can see the construction scope Laurent covers on the commercial construction and residential construction pages.
Choose the route that fits
The right contract route protects your budget, your programme and your peace of mind. Laurent is Alexandria-based and delivers projects across Egypt. Start your project, tell us what you have so far, and we will help you choose the route that suits it.
