15th April, 2020

23 CDM Regulation Questions Answered (FAQs)

What are the CDM regulations? Who is a principal contractor? What does the client need to do? Who can be the principal designer? There are lots of frequently asked questions that we often respond to regarding CDM, so we have dedicated this blog post to answer the most common questions.

23 CDM Regulation Questions Answered (FAQs) header image

What are the CDM regulations? Who is a principal contractor? What does the client need to do? Who can be the principal designer? There are lots of frequently asked questions that we often respond to regarding CDM, so we have dedicated this blog post to answer the most common questions.

We will also link out to other resources and posts for more in-depth explanations, and provide you with some free CDM tool and guides.

Need to find out about CDM? Start with our FAQ's!

CDM FAQ's

What are the CDM regulations?

CDM stands for the Construction (Design & Management) Regulations 2015. The CDM regulations apply to all construction work and are a legal requirement in Great Britain. The regulations place duties on all key duty holders involved in a project, intending to ensure that work is carried out safely and without risk to health.

Do the CDM regulations apply to my construction project?

Yes. CDM applies to all construction projects, no matter how big or small. If you are having construction work carried out, CDM will apply.

Who needs to be involved with CDM?

The CDM regulations place duties on all workers, and 5 key duty holders. The client, the principal designer, the principal contractor, designers, and contractors. Everyone involved in the project is likely to have one, or more, duty holder requirements.

What is a CDM notifiable project?

A notifiable project under CDM is any project lasting more than 500 person-days, or any project with more than 20 people at any time that lasts more than 30 days. Notifiable projects don't need to be treated differently now (unlike under the previous 2007 version of the regulations), but they do need to be notified to the HSE.

What happens if you fail to comply with CDM?

Failing to comply with CDM could mean that work on your project is stopped. It could also result in enforcement action, fines and prosecution. Find out more in 95 CDM 2015 Prosecutions (Breaches, Fines And Prison Time).

Client FAQ's

Who are CDM clients?

A client is anyone having construction work carried out for them. If you ask a contractor to carry out work or hire a designer to plan for a project, you are the client under CDM.

Why do clients have duties under CDM?

Clients often have a big say in how things are managed, even if they don't manage the work themselves. For example, they will choose the contractor, set the budget, and even set deadlines. All of these choices can have a big impact on health and safety on site. Rushing work because of an unrealistic timeframe or selecting a contractor who is not competent to do the work can be a recipe for disaster. Everyone has to do their bit under CDM to create a safe site, including clients.

Who are CDM domestic clients?

You are a domestic client if you are having work carried out which is not connected with running a business. Usually, this means arranging for work to be carried out on the property where you or a family member lives. If you are a domestic client, some of the client duties will transfer to other members of the project team.

What are the CDM client duties?

Client CDM duties include appointing other duty holders and making sure duties are carried out, allowing sufficient time and resources, and ensuring relevant information is prepared and provided. If a client fails to make the necessary appointments, they can become responsible for the additional duties.

What happens if there is more than one client?

If there is more than one client, then all of the clients may be considered to have duties under CDM. All of the possible clients can identify and agree who the clients are, and optionally, decide that only one of them should be responsible for carrying out the requirements of the client duties under CDM. All clients must still cooperate with everyone involved in the project and provide any relevant information for the project.

Principal Designer FAQ's

Who is the principal designer?

The CDM principal designer is the designer with overall control of health and safety during the pre-construction phase. This will often be the main architect. There can be many designers, but only one principal designer. The principal designer is appointed by the client, or for domestic clients, the appointment may happen automatically.

What are the principal designer's duties?

The principal designer has responsibilities for preparing and providing information, and planning, managing and monitoring the pre-construction phase health and safety arrangements. This includes identifying and controlling risks during project preparation, and ensuring other designers carry out their duties.

Does every project need a principal designer?

Most projects. The principal designer is required on projects with more than one contractor (including subcontractors and contractors not appointed by the client). Because most projects (including small projects) involve more than one contractor are some stages, a principal designer is usually required.

Principal Contractor FAQ's

Who is the principal contractor?

The principal contractor is the contractor in overall control of the construction phase. This will often be the main contractor. There can be many contractors, but only one principal contractor.

What are the principal contractor's duties?

Principal contractors are responsible for planning, managing, monitoring and coordinating the construction phase of the project, including preparing documents, organising, cooperating, managing and liaising with other duty holders. They must ensure site inductions are provided, prevent unauthorised access, provide welfare facilities and consult and engage workers on health and safety matters.

Does every project need a principal contractor?

Most projects. The principal contractor is required on projects with more than one contractor (including subcontractors and contractors not appointed by the client). Because most projects (including small projects) involve more than one contractor are some stages, a principal contractor is usually required.

Designer FAQ's

Who is a designer under CDM?

Any person preparing or modifying designs for a building, product or system relating to construction work is a designer under CDM. Examples include architects, engineers, design & build contractors, manufacturers, and sometimes clients and contractors. Any person or business carrying our design work on a project, no matter the type, size or duration, has designer duties under CDM.

What are designer duties?

As CDM duty holders, designers must eliminate, reduce and control foreseeable risks that may arise from the design during construction or future maintenance. Designers must also provide information to other members of the project including information for the pre-construction information and health and safety file.

Contractor FAQ's

Who is a contractor under CDM?

Contractors are those who carry out the construction work. This could be a scaffolder, a bricklayer, an electrician, or the main contractor. As with designers, there can be many contractor duty holders on a project. Any person or business carrying our construction work on a project, no matter the type, size or duration, has contractor duties under CDM.

What are contractor duties?

Contractors duties are to plan, manage and monitor the construction work under their control to that is carried out safely. They must also coordinate their activities with other contractors, and comply with directions from the principal contractor and principal designer. On single contractor projects (where there is no principal contractor) the single contractor has some extra duties including creating the construction phase plan and managing the construction phase.

Document FAQ's

What is the pre-construction information?

The pre-construction information should be available on every construction project. It is the first CDM document that will be produced, as it is required before work starts on site. It includes information about the project, arrangements and the client brief. It should also include health and safety information about hazards on the site. This will be information like surveys and plans already in the client's possession or obtained by the client. It may also include information from any existing health and safety file. The client is responsible for providing the pre-construction information, assisted by the principal designer.

What is the construction phase plan?

The construction phase plan is also required on every construction project. It needs to be produced by the principal contractor, or if there is only one contractor, by the single contractor. The construction phase plan must be developed before work starts on site. It contains information on how health and safety will be managed throughout the construction phase. This document should be added to if new trades start and additional activities or arrangements need to be addressed.

What is the health and safety file?

The health and safety file is the final document to be produced under CDM. This document is handed over to the client on project completion. The health and safety file must be produced on any project with more than one contractor (including subcontractors). It contains health and safety information needed for future use, cleaning and maintenance of the building or structure. It is created throughout the project by the principal designer, with information gathered from the principal contractor, other designers and contractors.


If you need help complying with CDM duties, get our free CDM duty holder guides for more support. And check if your project is CDM ready with the CDM compliance checklist.

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This article was written by Emma at HASpod. Emma has over 10 years experience in health and safety and BSc (Hons) Construction Management. She is NEBOSH qualified and Tech IOSH.

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