The standard construction contract in the UK, such as JCT 2005, is designed to balance time, quality and cost. Typically, the contract documents consist of a bespoke design described by a full package of drawings and a specification describing quality, techniques and materials. These enable a contractor to offer a fixed price for the work and establish a programme and the aim is to provide a level of financial security that leaves little to error or to contingent forces. That, at least, is the theory. In practice, there are few contracts that run as smoothly as the theory suggests, which accounts for the myriad case law in this area.

In preparing the contract documents, an architect conventionally begins their work by acting as agent for the client. Once appointed, s/he develops the brief with the client and/or users, designs the building and guides the scheme through the regulatory system, describing it in sufficient detail to allow a contractor to arrive at an accurate cost. After this, the ways in which a building can be procured can vary considerably. This article focuses on what happens under a Design and Build (D&B) contract.