CDM 2015
Duty Holder Guide


cdm 2015 Designer

Every designer involved in a construction project has duties under CDM. A designer is an organisation or individual that prepares or modifies a design for any part of a construction project, including the design of temporary works, or who arranges or instructs someone else to do it.

Designers have several duties under CDM, and must also provide information to the principal designer. In this guide, we will take you through your responsibilities step-by-step. We will also link you to tools, resources and checklists to help you carry out your role.


Designers can be architects, consulting engineers, interior designers, temporary work engineers, chartered surveyors, technicians, specifiers, principal contractors and specialist contractors. Designers must understand and be aware of significant risks that construction workers can be exposed to, and how these can arise from design decisions.

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Pre-Construction Phase
Before Construction Starts

The pre-construction phase is all the work that happens on a project before any work starts on site. This is the very earliest stage of a project and may also be referred to as the planning phase of the project. It's when designers and contractors are selected, and you plan and prepare for the project.


Designers and anyone they engage to help with design work must have the appropriate skills, knowledge, training and experience to do the work.

The term design includes drawings, design details, specifications, bills of quantity and calculations prepared for the purpose of a design. The scope of a designer under CDM applies to more than architects, and can include engineers, quantity surveyors, temporary work engineers, interior designers and often contractors, commercial clients and any other person who specifies or alters a design.

CDM duties will apply to you as soon as you are appointed and designs are started. It does not matter whether planning permission or funds have been secured, or if the client is a domestic client, CDM designer duties still apply.

Make clients aware of duties

As a designer, you must not start work in relation to a project unless you are satisfied that the client is aware of their client duties under CDM.

You can check the client is aware of their duties through early meetings or project discussions with the client.

On projects with more than one contractor, the client must appoint a principal designer. On these projects the principal designer will inform the client of their duties. You should check who the principal designer is, and seek confirmation from the principal designer that the client has been made aware of their duties.

Where the project is notifiable, check that the client has completed and submitted an F10 notification. Use our free CDM notification calculator to check if the project needs to be notified.

If you are working for a domestic client, some of their duties transfer to other members of the project team.

Identify, eliminate and control foreseeable risks

Designers should identify, eliminate, reduce and control risks in their own design, and the overall project design. Consider the risks people may be exposed to during construction and use of the building or structure you are designing.

Throughout the design process question:

  • If you can get eliminate the hazard altogether
  • If not, how can you reduce or control the risks, so that harm is less likely and severity of harm less serious

Designers should apply the general principals of prevention.

You are not expected to eliminate all risks, but you do have a duty to eliminate risks where you can, and reduce or control them where they cannot be eliminated.

Consider the pre-construction information

You must take account of the pre-construction information provided to you by the client or the principal designer. This will contain key information you will need in order to carry out your design.

Check you have all the information you need:

  • What information do you need?
  • Why do you need it?
  • Who will you get it from?

The pre-construction information will have details of site hazards, and other designs that may impact your work. This could include information on the site conditions, existing structures, services, and other constraints. It will also include information on the project team and others you need to communicate with.

If there is any information missing that you need, you should contact the client or principal designer in order to obtain it. There should be suitable arrangements in place to receive the information you need, check this with the principal designer and establish who is obtaining the information and timeframes for receiving it.

Provide design information

Designers must provide health and safety information relating to their design, including any unusual remaining risks and details of the key assumptions and decisions they have made, to other duty holders.

You should provide information to the principal designer, this will include:

  • Information about significant or unusual risks associated with your design that cannot be eliminated, for inclusion in the pre-construction information
  • Information to take into account for the health and safety file, such as information that could be of future use to the client or end user in the use, maintenance or future construction work on the structure

You should also provide information to other designers and contractors.

Information may include temporary works or sequencing required where these are not obvious to a competent contractor, design loads and specifications, and any survey or report obtained that could be useful to others in the management of health and safety.

Arrangements for sharing design information should be agreed with the principal designer (or client where there is no principal designer on single contractor projects), so that information can be shared in a clear and concise way.

Cooperate with other duty holders

Designers should provide regular updates, including information about issues or design changes that could potentially impact on health and safety, considering their own design and the impact of other design work for the project.

Just as you need to provide health and safety information relating to your design, you should also expect to receive information from other duty holders that may impact your work.

Designers should regularly talk and listen to each other throughout the design period. Regular communication will allow work to be coordinated and the impact of how designs interact and influence health and safety can be assessed.

Design reviews may be carried out to enable the project team to focus on health and safety matters along with other aspects of the project. These reviews may involve contractors and the client who can also have a valuable input. Contractors knowledge and experience about the practicalities of building the design can be taken into account.

Advise on time and resources

Clients have a duty to allocate sufficient time and other resources.

Designers can assist with estimating the period of time required to complete work or work stages during the pre-construction phase, as they may have a better knowledge of the time requirements at key stages of the project.

You should communicate with the principal designer and client any decisions taken about design, technical and organisational issues during the pre-construction phase, that may impact estimations of the time needed to complete certain items or stages of work.

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Construction Phase
When Work Starts On Site

The construction phase is when work that has been planned begins on site. It's when the site gets set up and the construction work could include demolition, maintenance and/or building activities.

Liaise during the construction phase

Designers should liaise with the principal contractor and other designers throughout the construction phase.

You should be available to answer any questions or queries regarding your design and any ongoing design work carried out during the project.

There may be a need to carry out design reviews throughout the project in order to focus on areas of the design where there are health and safety risks requiring resolution, or where there are changes to requirements or designs.

The duties for eliminating and controlling risks, providing information and cooperating with other duty holders continue throughout the construction phase.

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Post-Construction Phase
Project Completion

The post-construction phase is what happens at the end of the project. This may also be referred to as the handover phase of the project. It's when the construction work finishes and the project is signed-off and handed over the client.

Contribute to the health and safety file

You should provide information for inclusion in the health and safety file. Designers have a duty to ensure appropriate information is included in the health and safety file.

The health and safety file is produced by the principal designer and you need to provide them with any relevant health and safety information for inclusion in this document.

Requirements for the health and safety file, including its structure, content and format, should be identified before the construction phase and communicated by the principal designer.

The file contains the information needed to ensure the health and safety of anyone carrying out any future construction, demolition, cleaning or maintenance work on the building or structure.

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