- Project plans
- Project activities
- Legislation and standards
- Industry context
Last edited 06 Dec 2020
Optimised contractor involvement
The subtle difference between ECI and OCI is that in ECI, a contractor’s skills are introduced early into a project to bring design buildability and cost efficiencies to the pre-construction phase. In OCI, contractors are brought in at a stage that is late enough for the target price to be quite firm, but early enough for them to be able to influence buildability and value engineering.
ECI has been used on by many public sector construction clients, however, some clients have been reluctant to adopt the strategy because of concerns associated with appointing contractors before permissions such as planning have been granted, and issues to do with attracting accurate and competitive prices from contractors when the design is not yet well advanced.
The OCI approach optimises contractor involvement, rather than simply trying to make it as early as possible, waiting till a point when the contractor is more likely to be able to offer an accurate and competitive price.
The contractor input into the design under OCI generally takes place post contract award, whereas in ECI, it takes place pre-contract award, under an arrangement such as a Pre-Construction Services Agreement.
The OCI approach may adopt a two stage selection process. The first stage is based on an assessment of the contractor’s technical and quality competence. The second stage involves the shortlisted tenderers carrying out a review of the client’s design. The tenderers then submit their final proposals, including a target price.
 Find out more
 Related articles on Designing Buildings Wiki
Featured articles and news
Prioritising tax considerations.
The four D creative process: discover, define, develop and deliver.
National Cyber Security Centre initiative is announced.
Reviewing trends and projections.
Legislation will establish initiatives to move towards net zero.
How to document contractor employment status.
Tech tools to help manage people and space post-pandemic.
A style that ranges from mock Tudor to arts and crafts to the 'Wrenaissance'.
Free guide from Secured by Design.
BREEAM strategy for sustainability and the circular economy.
Free tool to improve the construction programming process.
Are buildings doing what they're supposed to be doing?
Cities with quick access to everything by foot or bike.
The pressures and pinch points of global destinations.