New industry survey sets out recommendations for Contractor Design Portions reform

Improving the use of Contractor Design Portions is based on responses from 381 construction professionals across Scotland, representing a wide range of roles and organisations. Its findings reveal strong and consistent concern that the current approach to CDPs is undermining construction quality and requires urgent reform.

Contractor Design Portions are commonly used where specialist design input is required for specific elements of a project. However, the survey found widespread agreement that CDPs are too often used inappropriately, particularly as a mechanism to transfer commercial risk, leading to poorly coordinated designs, late changes, and in turn, reduced build quality.

In response, the CQIC has set out 19 practical recommendations aimed at improving how CDPs are procured, designed, coordinated, and reviewed throughout the project lifecycle.

Key recommendations include:

 *   Using CDPs only where specialist design expertise is genuinely required, not as a means of transferring risk
 *   Identifying CDP requirements as early as RIBA Stage 1, with clear justification for specialist input
 *   Appointing a Lead Designer responsible for coordinating all CDP elements and ensuring compatibility across the design
 *   Completing CDP designs alongside other design work and no later than RIBA Stage 4
 *   Clearly defining CDP responsibilities using a Design Responsibility Matrix and performance specifications

The recommendations are mapped against the Royal Institute of British Architects (RIBA) Plan of Work stages to support practical implementation and are supported by analysis of barriers to change and how these can be addressed.

Colin Campbell, associate director at infrastructure body the Scottish Futures Trust and who co-chairs the CQIC, said: “Recent public inquiries have shown that incomplete and poorly coordinated design has a direct and serious impact on construction quality.”

“The industry response to this survey is clear and unified: the current approach to Contractor Design Portions must change if we are to deliver safer, higher-quality, and more sustainable buildings.”

Iain Kent, co-chair of the CQIC, who led the working group that developed the recommendations, added: “The report aligns closely with the Scottish Government’s response to the Grenfell Inquiry, reinforcing the need for improved design coordination, accountability, and regulatory compliance across the sector.

“The CQIC is urging employers, designers, contractors, sub-contractors, and all organisations involved in procuring and delivering construction projects to review the findings and implement the recommendations where appropriate.

“The full report includes detailed survey results, analysis by profession and organisation type, and appendices setting out the survey data and mapped recommendations.”

Stuart Parker, managing director of Morgan Sindall Scotland, added: “Over the years, CDP has become a widely used approach to design in construction. It has an important part to play in the delivery of high-quality facilities but it is important that it is used in a responsible way and not just to cut fees or to pass on risk or design responsibility.

“The CQIC work to show how CDP can be used well to support quality outcomes is very welcome given that it is based on feedback and input from across the sector.”