The JCT Design and Build Contract is designed for construction projects where the contractor carries out both the design and the construction work.
Design and build is a generic term describing a procurement route in which the main contractor is appointed to design and construct the works.
The appeal to clients is it gives a single point of responsibility for delivering the entire project. Some clients however consider it is only appropriate for simple projects, where design quality is not the main consideration.
A contractor can either be appointed to carry out all of the design work, or if the client wishes to have greater influence over the design, a concept design and outline (or performance) specification can be prepared by a consultants employed by the client, and then the contractor is appointed to complete the design and carry out the construction.
If the contractor is appointed at the start of a project (so that they can contribute to the development of the design from the beginning), they work with a design team (who may be employed either by the contractor or by the client at this stage) to develop the design, on the basis of which a fixed price is then negotiated.
Design and build contracts can be awarded on a fixed-price, lump-sum basis, but price certainty is then dependent on not making any subsequent changes as these could prove to be expensive (as prices charged by the contractor for those changes will not be subject to competition).
Features of projects using the Design and Build Contract:
The scale of design work need to be carried out by the contractor can vary greatly on design and build projects. Sometimes the contractor will complete a design based on a concept provided through the employer’s advisers. Other instances may call for the contractor to be responsible for producing and completing the design right from the outset, either through their in house team or employing their own specialist designers.
The design requirements and responsibility of the contractor in design and build projects go beyond that covered in a traditional contract with a contractor’s designed portion. Adequate time and care needs to go in to detailing the employer’s requirements so that the obligations of the contractor with regard to design is clear.
The employer normally uses an agent (either external consultant or employee) to administer the contract.