Who is responsible for design management during the operational phase of construction projects and what does their responsibility cover? Zacharias Fotos MCIOB explains
What you will learn in this CPD
- Why design responsibility should be considered by activity rather than organisation
- How responsibility is allocated and evidenced through project documents
- Why responsibility often overlaps between consultants, contractors and specialists
Design remains one of the largest sources of risk on construction projects. HKA’s Eighth Annual CRUX Insight Report, published in November 2025, found incorrect design was the leading cause of claims and disputes among the distressed European projects analysed, affecting 30% of the 583-project sample. Behind many sits a simple question: who was responsible for the design?
There is rarely a single answer. Design is distributed across consultants, contractors, specialists and manufacturers, with different parties responsible for different decisions, outputs and interfaces.
This CPD builds on our January 2026 CPD on BS 7000-4:2024, moving from organisational design governance to the practical allocation of design responsibility on live projects. It is written from a design management perspective rather than as legal advice. CDM dutyholder duties operate alongside contractual responsibilities, but are outside this scope and will be covered in a later CPD.
Design responsibility follows activities, not organisations
Project teams often assume responsibility moves with an appointment: from consultant to contractor or contractor to specialist. It does not move merely because another party becomes involved. Each party remains responsible for the activities allocated through its appointment, contract or subcontract.
The first question is therefore not only “who is responsible?”, but “who is responsible for what?”
Different parties may establish design intent, develop the technical solution, coordinate interfaces, review information or approve information for construction. These activities are frequently grouped together as “design development”, although they may sit with different organisations and do not necessarily transfer together.
Responsibility emerges from consultant appointments, scopes, the building contract, employer’s requirements, contractor’s proposals, specialist subcontracts and subsequent instructions. Novation, contractor’s designed portion and phased procurement may alter those allocations.
Ideally the design responsibility matrix is agreed early, aligned with consultant and specialist scopes and incorporated into the relevant appointments. But the matrix records and communicates responsibility; it does not independently override the contract. Its status depends on the contractual hierarchy and any order of precedence, so an allocation in a design responsibility matrix, employer’s requirements or technical scope may be overridden by a higher-ranking term.
This can be easily missed because project teams commonly work from matrices, scopes and technical schedules, whereas an adjudicator or tribunal will examine the contractual documents as a whole.
Two questions must be answered together:
- What design activity is being undertaken?
- Where has responsibility for that activity been allocated?
These questions should be revisited as the project develops. An agreed Stage 3 design responsibility matrix may no longer reflect the position after novation, specialist appointments or design changes.
Responsibility often overlaps before it transfers
The greatest risk often sits at the interfaces between packages.
A firestopping specialist may select and develop project-specific details based on a manufacturer’s tested system, while the fire engineer defines the required performance, the architect coordinates compartment lines and the MEP designer defines the service penetrations. Each party may complete its own scope, yet responsibility for confirming that the combined detail maintains the required fire resistance may remain unclear.
Notes such as “by specialist design” or “refer to contractor’s design” may show where further information is expected, but do not replace allocation through scopes, appointments and the design responsibility matrix. The design manager’s objective is to ensure every significant interface has a named owner.
Four assumptions that create design risk
1. Appointing a specialist transfers design responsibility
Not necessarily.
Appointing a specialist does not automatically remove responsibility from the party that established the original design intent. A specialist may develop calculations, fabrication drawings or product-specific details while another party remains responsible for the design criteria on which that work relies. Unless responsibility is expressly reallocated, both may retain responsibility for different aspects of the design.
Good practice: Clearly define the specialist’s scope, design boundaries, assumptions, deliverables and interface responsibilities.
2. Reviewing information transfers responsibility
Not necessarily.
Reviewing or accepting information does not usually transfer responsibility for its technical content. A design manager may review for coordination, a consultant may review design intent, and a client may review a commercial or aesthetic proposal.
Problems arise when comments such as “approved”, “accepted” or “no further comments” are interpreted as adoption of the underlying design. Review should be distinguished from verification, technical acceptance and formal adoption.
Good practice: State the purpose of the review and whether it includes verification or adoption.
3. Without design PI insurance, there is no design responsibility
Incorrect.
Design responsibility arises from the activity undertaken and obligations accepted, not from whether PI insurance is held. A sketch, marked-up drawing, RFI response, or technical decision may amount to design activity.
PI insurance may respond to a claim but does not create or remove responsibility. Inadequate cover can increase exposure.
Good practice: Before providing or receiving design input outside an agreed scope, confirm authority, competence and insurance.
4. Novation transfers all previous design responsibility
Not necessarily.
Novation changes the consultant’s contractual relationship, but it does not automatically mean previous decisions, assumptions or unresolved issues have been reviewed and adopted.
Risk arises where design remains unfinished, earlier work is changed or assumptions are carried forward without a named party responsible for closing them.
Good practice: At novation, record outstanding decisions, assumptions and responsibility for completing the design.
Standards, contracts and the standard of care
Design responsibility is shaped by statutory duties, contractual obligations, and the standards and guidance used to manage and evidence design.
Relevant references include:
- BS 7000-4:2024, covering the management of design in construction.
- The JCT 2024 suite, including provisions relating to contractor design.
- RIBA Plan of Work 2020 responsibility matrix guidance.
- BS EN ISO 19650-2:2018, covering information management during project delivery.
- BS 8536:2022, covering design, manufacture and construction for operability.
- Building Safety Act 2022 and associated dutyholder requirements.
Legislation establishes duties; contracts and appointments allocate scope and standards of care; standards support their management and evidence. Once responsibility is identified, the next question is the standard against which it is judged.
Standard of care: reasonable skill and care
Most consultant appointments require reasonable skill and care. The question is not simply whether the design contained an error, but whether the designer acted as a reasonably competent professional would in the same circumstances.
If an architect omits a door from a schedule, recovering resulting delay or additional cost would require evidence that the schedule fell within the architect’s scope and the omission breached the required standard and caused the loss. The assessment may also consider whether others should have identified the issue or mitigated its consequences.
A fitness-for-purpose obligation is different. It may require the design to achieve a specified outcome even where the designer exercised reasonable skill and care.
Two project scenarios
Firestopped service opening in a drylining partition
The MEP designer established the size and location of a service letterbox through a fire rated drylining partition. The firestopping specialist selected a suitable tested proprietary system, while the drylining manufacturer confirmed the framing and opening detail. The architect adopted the detail and coordinated with the ceiling void and surrounding construction.
Later, an additional service penetration was introduced adjacent to the letterbox. The proposed location fell outside the minimum separation permitted by the firestopping manufacturer’s test evidence, and the MEP designer had to relocate the service to remain within the tested configuration. The firestopping specialist confirmed compliance and the architect updated the coordinated information.
A local design change can affect several other packages without transferring responsibility for them. Change control should identify each consequential design task, assign it to the appropriately appointed designer and record the evidence needed before the revised interface is accepted.
Specialist sprinkler design within an MEP subcontract
The main contract and MEP subcontract placed responsibility for the Stage 4 MEP design, including sprinklers, on the MEP contractor. The MEP contractor then appointed a sprinkler specialist to develop the sprinkler layout, calculations and technical details.
The specialist was responsible to the MEP contractor for that work, but its appointment did not remove the MEP contractor’s upstream responsibility. The MEP contractor still had to ensure the sprinkler design met the project requirements and was coordinated with the wider MEP design, while the architect retained responsibility for the relevant ceiling setting out and architectural interfaces.
The key distinction is between who produces the specialist design and who remains responsible upstream. The specialist may design the system, but the MEP contractor remains accountable to the main contractor for incorporating that design into the overall package. The design responsibility matrix should show both levels.
Managing design responsibility in practice
Design responsibility should be managed as a live project control rather than recorded once and assumed to remain valid.
Design managers and project teams should:
- Align the design responsibility matrix with appointments, scopes and contractual documents at the point responsibilities are agreed
- Pause and revisit the design responsibility matrix after novation, RIBA stages, specialist appointments, or material design changes
- Give significant interfaces a named owner
- Distinguish between review, verification and adoption
- Resolve inconsistencies before information is used for procurement or construction
The central question is not simply who produced a drawing, but who established the requirement, developed the solution, coordinated its interfaces and accepted subsequent changes. Effective design management makes those distinctions visible before assumptions become design risk.
Zacharias Fotos MCIOB PMP® ARB is senior technical coordinator at Mount Anvil. This is the second in a series on design management; a further CPD will cover CDM dutyholder duties.
