A Guide To The Design Process
Concept Design generally involves the application of a design ‘idea’ to the practical provision of a facility. It represents a phase where sufficient design concepts are developed for the Client to be able to establish the feasibility of the project, the development potential of a site, or to be able to select a particular conceptual approach that the Client wishes to pursue. The Concept Design phase may be used to define or verify the Brief, and may often involve the testing of different approaches/options. During this phase, ideas (concepts) are developed through open interaction by the team of the key elements of the project. At the end of this phase, the basic building blocks of the project are defined in general terms and co-ordinated between the design disciplines.
Concept and Preliminary Design phases are often combined on smaller projects.
Preliminary Design generally involves the further refinement of the preferred Concept to facilitate testing it against inputs from the team, including cost estimates and regulatory approval. It may provide sufficient information for the communication of the design to a third party for marketing or consultation purposes.
During this phase the project concepts are developed into firm schemes, where the relationship and sizes of spaces and facilities are defined, and co-ordinated between the design disciplines. However, resolution of individual details that do not impact on the key elements are generally left for the next design phase. At the end of this phase, the project should be clearly defined.
Developed Design is the phase where every component of the design is investigated, verified and co-ordinated. This may involve production of detailed information including sketch details of all significant componentry and their inter-relationships. The Developed Design phase is where the individual technical experts prepare the necessary documentation to define the scope of all building elements, major input is required by all designers. The completion of the Developed Design is the critical point in a project. The scope of the project is fully defined and as a result, cost estimates can be prepared. Developed Design generally provides sufficient information for the client/user to clearly understand the aesthetics and functionality of the building, internal spaces and facilities.
On many projects the Developed Design documentation is issued for Building Consent and/or ‘Guaranteed Maximum Price’ (GMP) tender. Coordination between the design discipline is therefore critically important at the end of this stage.
Detailed Design generally provides a level of documentation that clearly defines the design, specification and extent of all building elements. The design should be comprehensively coordinated with other disciplines. However, the documents produced in this phase may not directly be able to be built from. Changes to anything but detail at this stage are very disruptive, expensive and often result in further problems as by now the project has become very complex and it is hard to identify all the ramifications of changes. Detailed Design is the phase most commonly used to obtain a Tender for the construction of the works.
Construction Design is where the requirements defined in Detailed Design documents are integrated with construction requirements such as site conditions, proprietary and performance design elements, erection requirements and fabricated shop drawings to create drawings that can be directly ‘built’ from. (Note: Shop drawings are produced during this stage).