Why principal designers matter

1 Introduction
2 The role of the principal designer under CDM 2015
3 Early involvement in design
4 Pre-construction information
5 Design risk management and competence
6 CDM principal designer and Building Regulations principal designer
7 Building safety, higher-risk buildings and information management
8 Coordination with the principal contractor
9 Demonstrating effective CDM management
10 What clients should expect
11 Conclusion
12 Related articles on Designing Buildings

[edit] Introduction

The principal designer has an important role in managing health and safety risks during the design and planning of construction projects. Under the Construction (Design and Management) Regulations 2015 (CDM 2015), the principal designer is responsible for planning, managing, monitoring and coordinating health and safety during the pre-construction phase. The role is intended to ensure that foreseeable risks are considered early enough for them to be eliminated or reduced through design, and that relevant information is communicated to those responsible for construction, maintenance and future use.

The introduction of the Building Regulations dutyholder regime in England has established a separate principal designer role concerned with compliance with the Building Regulations. Although the two roles have related objectives, they have distinct legal duties and should not be confused.

[edit] The role of the principal designer under CDM 2015

Where a project involves, or is reasonably foreseeable to involve, more than one contractor, the client must appoint a principal designer and a principal contractor in writing. The principal designer must be a designer with control over the pre-construction phase and the skills, knowledge, experience and, where applicable, organisational capability necessary to perform the role.

The principal designer must plan, manage and monitor the pre-construction phase and coordinate health and safety matters during that phase. Duties include assisting the client with pre-construction information, ensuring cooperation between designers, coordinating the identification and management of foreseeable risks, and liaising with the principal contractor. The principal designer must also ensure that relevant information is included in the health and safety file and that the file is appropriately prepared, reviewed, updated and passed to the client.

The role is not limited to producing documents such as a risk register, pre-construction information or a health and safety file. Its purpose is to influence design decisions, coordinate the work of designers and help ensure that significant foreseeable risks are addressed throughout the design process.

[edit] Early involvement in design

The principal designer should be appointed as early as practicable, ideally during the concept design stage. Decisions made at this point can have a significant effect on the risks associated with construction, maintenance, alteration and eventual demolition. Early involvement allows the principal designer to identify hazards and influence the design before key decisions become difficult or costly to change.

Design risk reviews may consider whether significant hazards can be eliminated, whether access for construction and maintenance can be improved, whether work at height can be avoided or reduced, and whether demolition, temporary works and structural alterations have been adequately considered. Other issues may include asbestos, existing services, utilities, fire safety and constraints arising from the existing building or site.

The principal designer does not need to be the technical expert in every design discipline. However, they must have sufficient competence to understand the relevant risks, coordinate the designers and ensure that appropriate matters are identified, addressed and communicated. The role is therefore one of design risk management and coordination rather than simply document production.

[edit] Pre-construction information

Pre-construction information (PCI) provides designers and contractors with information about the project, the site and existing hazards that may affect health and safety. The client has duties to provide relevant information, with the principal designer assisting the client in obtaining, assembling and communicating it and providing relevant information to designers and contractors within their control.

Depending on the project, PCI may include existing drawings, asbestos surveys, structural assessments, fire safety information, details of existing services and utilities, previous health and safety files, site investigations, surveys, access constraints and information about known hazards.

PCI should be relevant to the project and usable by those who need it. A collection of documents is not, by itself, evidence that risks have been adequately managed. The information needs to be interpreted so that its implications for design, construction sequencing, access, demolition and construction methods are understood. For example, asbestos survey findings may affect the design, the sequencing of work and the arrangements required before materials can be disturbed.

Information gaps should be identified and addressed where they could affect the design or safe delivery of the project. The principal designer should coordinate the relevant parties to ensure that significant risks and constraints are understood before construction begins.

[edit] Design risk management and competence

Effective design risk management focusses on significant and foreseeable risks arising from the project, rather than relying on lengthy lists of generic hazards. The general principles of prevention should be applied when considering how risks can be avoided or controlled. The priority is to eliminate hazards through design where reasonably practicable, reduce risks that cannot be eliminated, and communicate information about significant residual risks to those who need it.

Risk information should support design decisions and coordination. A risk register can be useful when it records project-specific hazards, the measures taken to address them, outstanding actions and the information that needs to be communicated. It is less useful when it merely repeats generic hazards without influencing the design or the management of the work.

Competence is central to the role. A client should consider whether the proposed principal designer has the skills, knowledge, experience and, where relevant, organisational capability appropriate to the project's nature, scale and complexity. A job title or general experience in construction does not, on its own, demonstrate competence to undertake a particular appointment.

[edit] CDM principal designer and Building Regulations principal designer

The CDM principal designer and the Building Regulations principal designer are separate legal roles.

Under CDM 2015, the principal designer coordinates health and safety during the pre-construction phase. The role applies in Great Britain and is concerned with protecting the health and safety of people affected by construction work, including those who construct, use and maintain the building.

In England, the Building Regulations dutyholder regime establishes a separate principal designer role for design work. The Building Regulations principal designer must plan, manage and monitor design work and coordinate matters relating to compliance with the applicable Building Regulations requirements. The duties apply to relevant building work under the English regulatory framework, with additional requirements for higher-risk building work where applicable.

The same individual or organisation may undertake both roles if the client makes the necessary appointments and the appointee has the competence and capability to fulfil each set of duties. However, fulfilling one role does not automatically satisfy the requirements of the other. Clients should establish clearly which appointments are being made, the responsibilities associated with each and how the relevant parties will cooperate.

The distinction is particularly important on projects where both regimes apply. The design team needs to coordinate health and safety risk management with the separate process for demonstrating compliance with the Building Regulations, without treating the two as interchangeable.

[edit] Building safety, higher-risk buildings and information management

The Building Safety Act 2022 introduced changes to the regulatory framework for building safety in England. For higher-risk building work within the scope of the regime, Building Regulations approval from the Building Safety Regulator is required before the relevant building work can begin. The process includes requirements concerning design information, competence, construction control, change control and demonstrating compliance.

Where applicable, changes to approved design information must be assessed, managed and recorded in accordance with the relevant procedures. The principal designer and other dutyholders need to understand how proposed changes affect the design, regulatory compliance and the information provided to the project team.

The golden thread of information is an important element of the building safety regime for relevant higher-risk buildings. It concerns maintaining accurate, accessible and reliable information about the building and its safety throughout the applicable lifecycle. It is not simply a digital filing system: information must be managed so that it can support decisions and demonstrate how relevant building safety requirements are being addressed.

These requirements reinforce the importance of accurate design information, clear responsibilities and effective communication. The precise statutory requirements depend on the building, the work and the applicable regulatory regime.

[edit] Coordination with the principal contractor

The principal designer and principal contractor have complementary responsibilities under CDM 2015. The principal designer must liaise with the principal contractor throughout the principal designer's appointment and share information relevant to planning, managing and monitoring the construction phase. The principal contractor must take account of relevant design and risk information when planning and managing construction.

Cooperation is particularly important when designs change, unforeseen site conditions are discovered, construction sequencing is revised, additional work is introduced or new risks emerge. Information about changes and newly identified hazards needs to reach the relevant designers and construction personnel so that the implications can be assessed and appropriate action taken.

The transition from design to construction should therefore be managed as a continuing process of communication and coordination, rather than as a simple handover of documents. Effective liaison helps ensure that decisions made during design remain understood and that new information arising during construction is addressed.

[edit] Demonstrating effective CDM management

Producing pre-construction information, risk registers and a health and safety file does not, by itself, demonstrate effective compliance with CDM 2015. The key consideration is whether the project has been planned, managed and coordinated so that foreseeable risks are identified, eliminated or reduced where practicable, and relevant residual risks are communicated.

The principal designer should be able to demonstrate how health and safety considerations have influenced design decisions, how significant risks have been managed, how information gaps have been addressed and how relevant information has been communicated to the principal contractor and other parties. The arrangements should be proportionate to the project and focused on practical risk reduction.

[edit] What clients should expect

A principal designer should become involved early, understand the project and its constraints, review available information, identify gaps and coordinate designers in managing health and safety risks. They should challenge significant design risks, ensure that relevant residual risks are communicated, liaise with the principal contractor and support the preparation and maintenance of the health and safety file.

Where the Building Regulations principal designer role also applies, the client should ensure that the separate appointment and duties are understood and that the appointee can coordinate design work to support compliance with the applicable requirements. The extent of the arrangements should reflect the project's complexity and the relevant statutory obligations.