Guide
CDM 2015: your duties as a construction client
Your legal duties when commissioning construction work under the Construction (Design and Management) Regulations 2015. Covers appointing Principal Designer and Principal Contractor, providing pre-construction information, notification requirements, and the difference between commercial and domestic clients.
If you commission construction work, you are the client under the Construction (Design and Management) Regulations 2015 (CDM 2015). This applies whether you are a business, a public body, or a domestic homeowner.
As a commercial client, you have specific legal duties that cannot be delegated. You may appoint others to carry out tasks on your behalf, but you remain legally responsible for ensuring those duties are fulfilled.
This guide explains what you must do as a client commissioning construction work in Great Britain. Getting this right from the start will help protect workers on your project and avoid criminal penalties.
Are you a client under CDM 2015?
You are a client if you are having construction work done for you. This includes:
- Building new premises or extensions
- Refurbishing or fitting out existing premises
- Demolishing structures
- Major maintenance and repair work
- Installing mechanical, electrical or other services
- Commissioning work as a developer, property company or landlord
CDM 2015 distinguishes between commercial clients (businesses commissioning work in the course of their business) and domestic clients (individuals commissioning work on their own home for personal use).
Your core duties as a commercial client
CDM 2015 Regulation 4 places duties on commercial clients. You must fulfil all of these on every construction project, regardless of size:
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Make suitable management arrangements
Ensure the project is set up properly for health and safety. This means allowing enough time and allocating sufficient resources for the work to be planned, managed and monitored safely. Unrealistic timescales and inadequate budgets that force contractors to cut corners are a breach of your duties.
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Appoint competent duty holders
When you appoint designers, Principal Designer, contractors, or Principal Contractor, you must take reasonable steps to satisfy yourself they have the skills, knowledge, training, and experience to carry out their role safely. Ask for evidence of competence before appointing anyone.
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Provide pre-construction information
Share all relevant information about the site with your designers and contractors as soon as practicable. This includes existing drawings, asbestos surveys, ground conditions, underground services, and any previous health and safety file from earlier construction work.
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Ensure the construction phase plan is prepared
Before construction work begins, make sure a construction phase plan exists that sets out how health and safety will be managed on site. On multi-contractor projects, the Principal Contractor prepares this. On single-contractor projects, the contractor does.
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Ensure welfare facilities are provided
Construction workers must have access to adequate welfare facilities throughout the project: toilets, washing facilities, drinking water, and rest areas. You must ensure these are in place before work starts.
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Ensure the health and safety file is prepared
Make sure the Principal Designer prepares a health and safety file containing information needed for future construction work, maintenance, and demolition. At project completion, you receive this file and must keep it available.
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Take reasonable steps to ensure duty holders fulfil their duties
You cannot simply appoint people and forget about them. You must take reasonable steps to check that your Principal Designer and Principal Contractor are actually fulfilling their legal obligations throughout the project.
Appointing Principal Designer and Principal Contractor
If your project will involve more than one contractor at any time, you must appoint:
- A Principal Designer to coordinate health and safety during the design (pre-construction) phase
- A Principal Contractor to coordinate health and safety during the construction phase
These appointments must be made in writing. The appointment should clearly state the person or organisation is taking on the role and its associated duties.
When to appoint
Principal Designer: Appoint as soon as practicable, and in any event before the construction phase begins. Ideally, appoint them before design work starts so they can coordinate health and safety from the outset.
Principal Contractor: Appoint as soon as practicable, and in any event before the construction phase begins. They must be appointed before any construction work starts on site.
What happens if you do not appoint
If you fail to appoint a Principal Designer when required, you assume all Principal Designer duties yourself. Similarly, if you fail to appoint a Principal Contractor, you assume all Principal Contractor duties.
This is rarely practical for commercial clients. These roles require specific expertise in construction health and safety. Failing to make appointments does not remove the duties - it transfers them to you, making you directly responsible for complex health and safety coordination.
Who can be appointed
Principal Designer must be a designer with control over the pre-construction phase and the skills, knowledge and experience to fulfil the role. Typical appointees include:
- Architects with CDM experience
- Multidisciplinary design practices
- Lead consultants with design oversight
- Larger contractors with design capability
Principal Contractor must be a contractor. This is typically the main contractor managing the site. They must have skills, knowledge and experience in managing construction phase health and safety.
When you must notify HSE
Certain construction projects must be notified to the Health and Safety Executive (HSE) before the construction phase begins. This is the client's duty, though you may ask the Principal Designer or Principal Contractor to submit the notification on your behalf.
A project is notifiable if it meets either of these thresholds:
How to calculate the thresholds
30 working days with 20+ workers: Both conditions must be met. Count days when construction work actually takes place (not calendar days). The 20 workers must be working simultaneously at some point during the project, even if only for one day.
500 person-days: Multiply the number of workers by the days they work. For example:
- 10 workers for 50 days = 500 person-days (notifiable)
- 25 workers for 20 days = 500 person-days (notifiable)
- 5 workers for 80 days = 400 person-days (not notifiable on volume alone)
When in doubt, notify. There is no penalty for notifying a project that turns out not to meet thresholds. But there are serious penalties for failing to notify when required.
Providing pre-construction information
You must provide pre-construction information to every designer and contractor you appoint (or are considering appointing) as soon as is practicable.
Pre-construction information means information in your possession, or reasonably obtainable, that is relevant to the construction work. The earlier you provide this, the better designers and contractors can plan the work safely.
Gather and share this information at the start of the project:
What you should provide
The information you need to gather depends on the project, but typically includes:
- Existing drawings and structural information: As-built drawings, structural surveys, previous alterations
- Hazardous materials: Asbestos surveys are essential for buildings constructed before 2000. Also consider lead paint, contaminated land, hazardous chemicals
- Underground services: Location of gas, water, electricity, telecommunications cables
- Ground conditions: Ground investigation reports, drainage, contamination assessments
- Previous construction: Health and safety file from any previous construction work on the site
- Site constraints: Access restrictions, neighbouring uses, environmental factors
- Ongoing operations: If work is in an occupied building, information about how the business operates
If you do not have some of this information, say so. Designers and contractors need to know what information exists and what gaps remain, so they can obtain missing information themselves or factor the uncertainty into their plans.
Domestic clients: reduced duties
A domestic client is someone commissioning construction work on their own home for personal use, not as part of a business. For example, a homeowner having an extension built or their kitchen refurbished.
Domestic clients have reduced duties under CDM 2015. Their duties transfer automatically to the contractors:
- Single contractor project: The contractor takes on client duties
- Multiple contractor project: The principal contractor takes on client duties (or the contractor in control of the construction phase if no principal contractor is appointed)
Alternatively, a domestic client can enter a written agreement with the Principal Designer to transfer client duties to them instead.
What domestic clients still need to do
Although duties transfer, domestic clients should still:
- Choose competent contractors (look for relevant qualifications and membership of trade bodies)
- Provide any information they have about the property (old drawings, known asbestos, underground services)
- Allow reasonable time for the work to be done safely
- Keep the health and safety file at project completion
Landlords and property developers
Landlords commissioning work on rental properties are commercial clients, not domestic clients. The work is done in the course of their letting business.
Property developers commissioning work on homes they intend to sell are commercial clients. The work is done in the course of their development business, even though the end product is a domestic property.
Only if you are having work done on your own home for your own personal use are you a domestic client.
Common client mistakes to avoid
These are the most common ways clients breach CDM 2015:
- Not making written appointments: Verbal agreements are not sufficient. Principal Designer and Principal Contractor appointments must be in writing.
- Appointing too late: Principal Designer should be appointed before design work starts. Principal Contractor must be appointed before construction starts. Last-minute appointments undermine the whole purpose of CDM.
- Not checking competence: You must take reasonable steps to satisfy yourself that duty holders are competent. Simply accepting someone's claim that they can do the job is not enough.
- Withholding pre-construction information: Failing to share what you know about the site creates risks. Designers and contractors cannot plan safe work without understanding existing hazards.
- Setting unrealistic timescales: Pressuring contractors to complete work too quickly is a breach of client duties. Rushed work leads to accidents.
- Failing to notify: Not submitting F10 notification for notifiable projects is a criminal offence. If in doubt, notify.
- Ignoring the health and safety file: Not ensuring a file is prepared, or not keeping it after project completion, breaches client duties and creates risks for future work.
Penalties for failing to comply
Breaching CDM 2015 is a criminal offence. The Health and Safety Executive (HSE) can prosecute clients who fail to fulfil their duties. Penalties are severe:
HSE actively enforces CDM against clients. Recent prosecutions include clients who:
- Failed to ensure welfare facilities were provided
- Did not appoint competent duty holders
- Failed to notify projects to HSE when required
- Set unrealistic timescales that contributed to accidents
Beyond criminal penalties, CDM failures can result in civil claims from injured workers, increased insurance premiums, reputational damage, and difficulty winning future contracts.
Client duties checklist
Before your construction project starts, ensure you have:
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Identified whether you are commercial or domestic client
If you are commissioning work on your own home for personal use, you are domestic and most duties transfer to contractors. Otherwise, you are a commercial client with full CDM duties.
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Determined if the project needs Principal Designer and Principal Contractor
If more than one contractor will work on the project at any time, you must appoint both. If only one contractor throughout, these roles are not required.
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Made appointments in writing before relevant phases begin
Principal Designer before design work starts (or as soon as practicable). Principal Contractor before construction phase begins.
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Checked competence of all duty holders
Asked for evidence of skills, knowledge, training and experience before making appointments.
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Gathered and shared pre-construction information
Provided all relevant information about the site to designers and contractors as soon as practicable.
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Calculated whether project is notifiable
Checked if project exceeds 30 working days with 20+ simultaneous workers OR 500 person-days. If so, submitted F10 before construction starts.
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Ensured construction phase plan will be prepared
Confirmed that the Principal Contractor (or contractor on single-contractor projects) will prepare a plan before work starts.
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Ensured welfare facilities will be provided
Confirmed adequate toilets, washing, drinking water and rest facilities will be available before work starts.
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Planned to receive and keep the health and safety file
Made arrangements to receive the file at project completion and keep it available for future work.