The Role of Quantity Surveyors Across the RIBA Plan of Works

At the very start, the QS helps define the project’s objectives and budget. Initial cost advice and feasibility studies assess financial viability and highlight risks and opportunities. By establishing realistic budget parameters and clarifying the cost implications of strategic decisions, the QS lays a strong foundation for the project and ensures that early choices are informed and sustainable.

During the preparation and briefing stage, the QS works closely with the client and design team to refine the project brief. Feasibility studies are revisited, and procurement strategies are recommended to reflect programme, design control, and cost requirements. The QS ensures the project can progress efficiently and that the client’s priorities are clearly reflected in early decisions.

As the project takes shape, the QS produces a formal Cost Plan 1, breaking down the emerging design into elemental costs. Strategic value management ensures that the right decisions are being made from the outset. Cost risk and contingency allowances are developed alongside the design to maintain control and keep the project on track, allowing the client to make informed choices before significant resources are committed.

During spatial coordination, the QS updates the cost plan to reflect the more developed design, producing Cost Plan 2 and reviewing construction methodologies and material selections. Collaboration with the design team identifies opportunities for value engineering, optimising cost without compromising quality. Guidance on procurement and contract strategy ensures that the project is commercially sound and identified risk begins to be appropriately apportioned as the project progresses to technical design.

In the technical design stage, the QS prepares a comprehensive Cost Plan 3 aligned with the fully developed technical design. Tender documentation is reviewed and refined, and advice on contract selection is provided. By ensuring the project enters construction with a clear, well-defined scope and robust commercial framework, the QS mitigates commercial risks and strengthens cost certainty.

Throughout construction, the QS manages the commercial aspects of delivery. This includes administering the contract, valuing interim and final payments, and monitoring variations. Cost reports and cashflow forecasts allow the client to track expenditure and programme progress, maintaining transparency and control. SOCOTEC’s wider technical expertise, from quality inspections to materials testing, can be integrated at this stage to manage risk and ensure specifications are met.

As construction concludes, the QS supports a smooth handover, preparing and agreeing final accounts and resolving any contractual claims. 

Post-completion cost analysis and lessons learned workshops help capture insights for future projects and support long-term planning.