Last edited 22 Feb 2021

CDM 2015 principal designer duties

The Construction (Design and Management) Regulations (CDM Regulations) are intended to ensure that health and safety issues are properly considered during a project’s development so that the risk of harm to those who have to build, use and maintain structures is reduced. They were introduced in 1994 and revised in 2007. A further revision came into force in April 2015.

One of the key changes introduced by CDM 2015 is the replacement of the role of CDM co-ordinator (CDMC) with a principal designer (PD). The principal designer has responsibility for co-ordination of health and safety during the pre-construction phase. The reason for the change is to give responsibility for CDM during the design phase to an individual that has the ability to influence the design. Under the 2007 regulations, this role was often contracted out, resulting in extra costs, but the individual appointed was rarely properly embedded in the project team and so had little opportunity to influence the design.

Guidance published by the Health and Safety Executive in January 2015, defines principal designers as ‘…designers appointed by the client in projects involving more than one contractor. They can be an organisation or an individual with sufficient knowledge, experience and ability to carry out the role.’ This may be combined with other roles on the project, such as project manager or architect.

The guidance suggests that the role of principal designer includes:

In addition, domestic clients can choose to have a written agreement with the principal designer to transfer their duties to the principal designer.

The principal designer should be appointed as early as possible in the design process (if practicable at the concept stage) and at least before the start of the construction phase, so they have enough time to carry out their duties to plan and manage the pre-construction and construction phases. If a client fails to appoint a principal designer, the client must carry out their duties.

If domestic clients on projects involving more than one contractor fail to appoint a principal contractor and principal designer, those duties will fall to the designer and contractor in control of the pre-construction and construction phases. See CDM for self-builders and domestic clients for more information.

Guidance has been produced by the Construction Industry Advisory Committee (CONIAC) with small businesses in mind: Industry guidance for Principal Designers (PDF, 150 KB).

Legislative obligations to Client

A client who is unfamiliar with construction projects will need to be made aware that the CDM Regulations apply to their project.

Re-iterate that the CDM regulations 2015 prevent work continuing beyond very initial design work until a CDM co-ordinator is appointed.

Make the client aware that you are registered with the ARB and have to adhere to it’s Code of Conduct and as such you are required under this Code to inform the client that architects are subject to the disciplinary sanction of the Board in relation to complaints of unacceptable professional conduct or serious professional incompetence.

While as architects, such of the legislation will be bound into our scope of services and will be diligently carried out; its falls outside our scope of services to supply the client with exhaustive details. Therefore, recommend to the client to contact their legal advisors for comprehensive legal advise.

The CDM 2015 require Principal Contractors and Designers (as well as others involved in the project) to advise the client of their responsibilities regarding CDM.

Advise the client on the adequacy of revised sums and time allowed to give effect to H&S measures.

In February 2020, The Health and Safety Executive (HSE) announced new research to better understand the benefits and challenges of the principal designer role.

[edit] Related articles on Designing Buildings Wiki


Even the HSE does not understand these awful new regulations, for example on a domestic project with no designer, who assumes the principal designer duties ?

Designing Buildings Anywhere

Get the Firefox add-on to access 20,000 definitions direct from any website

Find out more Accept cookies and
don't show me this again