Do I Need a Principal Designer? CDM 2015 Explained
If you are planning construction, refurbishment or maintenance work and more than one contractor will be involved, the short answer is yes: you almost certainly need a Principal Designer. It is a legal requirement under the Construction (Design and Management) Regulations 2015 (CDM 2015), and the duty to appoint one sits with you as the client. This guide explains when a Principal Designer is required, who can take the role, what they actually do, and the risks of getting it wrong.
When do you need a Principal Designer?
Under CDM 2015, you must appoint a Principal Designer, in writing, on any project where more than one contractor is, or is likely to be, involved. This is the single trigger that most people miss. It does not matter whether the project is large or small, commercial or domestic, or whether it needs to be notified to the Health and Safety Executive. If there is more than one contractor, for example a builder and an electrician, the duty applies.
Two points are worth being clear about, because they are often confused:
More than one contractor triggers the appointment. A contractor is anyone who manages or carries out construction work. As soon as a second one is involved, you need both a Principal Designer and a Principal Contractor.
Notification is a separate threshold. A project is notifiable to the HSE, using form F10, only if the construction work will last longer than 30 working days and have more than 20 workers working at the same time at any point, or will exceed 500 person days. A project can require a Principal Designer without being notifiable. Do not use notification as your test for whether you need to make the appointment.
Who can be a Principal Designer?
A Principal Designer can be an organisation or an individual, but they must have the right skills, knowledge, experience and, if they are an organisation, the organisational capability to carry out the role. Crucially, the Principal Designer must be a designer who has control over the pre-construction phase. CDM 2015 was written on the assumption that the lead designer, often the architect or lead engineer, would take the role because they are already coordinating the design.
In practice, you have a few options. You can keep the role in-house with your lead designer, you can appoint an external Principal Designer consultant to hold the role for you, or you can keep it in-house but bring in a specialist CDM adviser to support your designer. Each route reaches the same legal outcome, and the right choice depends on your team’s competence and capacity. We cover the pros and cons of each in detail on our Principal Designer services page.
What does a Principal Designer do?
The Principal Designer manages health and safety during the pre-construction phase, which is the design and planning stage before work starts on site. The core duties under CDM 2015 are to:
- Plan, manage, monitor and coordinate health and safety throughout the pre-construction phase.
- Help the client gather and share the pre-construction information that designers and contractors need.
- Work with every designer to eliminate foreseeable health and safety risks, and reduce or control any that cannot be designed out.
- Make sure everyone involved in design cooperates and communicates.
- Liaise with the Principal Contractor and pass on information about risks that will need to be managed during construction.
- Prepare and hand over the Health and Safety File at the end of the project.
The thinking behind the role is simple: the decisions made at the design stage have the greatest influence on whether a building can be constructed, used and maintained safely. Catching a risk on a drawing is far cheaper and safer than discovering it on site.
Principal Designer vs Principal Contractor: what is the difference?
These two roles are often mixed up because they sound similar and both are mandatory on multi-contractor projects. The difference is the phase they cover. The Principal Designer is responsible for health and safety during the pre-construction (design) phase. The Principal Contractor is responsible for health and safety during the construction phase on site. One organisation can hold both roles if it is competent to do so, which sometimes happens on design and build projects, but they remain two separate legal appointments with separate duties.
What happens if you do not appoint a Principal Designer?
If you do not make an appointment, the duties do not disappear. On commercial projects the client retains the Principal Designer duties by default, which means you carry the legal responsibility yourself, usually without the expertise to discharge it. On domestic projects the role automatically passes to the designer in control of the pre-construction phase, or to the Principal Contractor.
Failing to appoint a competent Principal Designer is one of the most common CDM breaches the HSE finds. The consequences can include enforcement notices, delays, uninsured risk, and in the event of an incident, personal liability. Appointing the right Principal Designer early is the straightforward way to stay compliant and keep your project moving.
How Callsafe can help
Callsafe Services has acted as Principal Designer, and as CDM adviser to in-house Principal Designers, since the regulations were introduced. We can hold the appointment for you, support your own design team, or simply advise on the best route for a one-off project. To talk it through, see our Principal Designer services or contact us on 01889 577 701.
Frequently asked questions
Is a Principal Designer a legal requirement?
Yes. Under CDM 2015 the client must appoint a Principal Designer in writing on any project involving more than one contractor. If no appointment is made, the duties fall to the client, or on domestic projects to the designer in control of the pre-construction phase.
Do I need a Principal Designer on a small or domestic project?
If more than one contractor is involved, yes. The size of the project and whether it is domestic or commercial does not remove the requirement. On domestic projects the duty can pass to the designer or Principal Contractor if the client does not appoint one.
Can the same company be both Principal Designer and Principal Contractor?
Yes, provided it has the competence for both roles. They remain two separate appointments covering two different phases, the design phase and the construction phase.
Does my project need to be notified to the HSE?
Notification using form F10 is required only if the work lasts longer than 30 working days with more than 20 workers at once, or exceeds 500 person days. This is separate from the need to appoint a Principal Designer, which is triggered simply by having more than one contractor.