Commercial Refurbishment Contractors
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CDM 2015 client duties

Applies to
All construction work, any size
F10 threshold
Over 30 working days with more than 20 workers at once, or over 500 person-days
Enforced by
HSE

The Construction (Design and Management) Regulations 2015 apply to every building project, including a weekend office refresh. A business or public body that commissions the work is a commercial client, and carries legal duties of its own that cannot be handed to the contractor.

This page sets out those duties in plain terms. It is general guidance based on HSE's published material, not legal advice for a particular project.

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The client's duties, in short

Make suitable arrangements
Allow enough time and money for the work to be done safely, and make sure the people you appoint have the skills, knowledge and experience for it.
Appoint in writing
Where more than one contractor will work on the project, appoint a principal designer and a principal contractor in writing, as early as you can.
Provide information
Give designers and contractors the pre-construction information you hold or can reasonably get: drawings, asbestos surveys, services records, how the building is used.
Check before and after
Make sure a construction phase plan exists before work starts, welfare facilities are provided, and a health and safety file is prepared and kept.

Register of client duties

ItemScopeGuide cost
Appoint principal designerWhere more than one contractor is involved; in writingBefore design starts
Appoint principal contractorWhere more than one contractor is involved; in writingBefore construction starts
Pre-construction informationIncluding asbestos, services and structureAs early as possible
Construction phase planDrawn up by the principal contractor or contractorBefore work starts
F10 notification to HSEOnly if the project crosses the thresholdAs soon as practicable before work
Health and safety filePrepared by the principal designer; kept by the clientAt handover, kept for the building's life

Summarised from HSE guidance on CDM 2015 and the Regulations themselves. If you do not make the appointments where they are needed, the client must carry out those roles. A guide, not a quote. Build a budget in the cost plan.

What the duties mean on a refurbishment

You are the client even if a fit-out firm "does everything"

A design and build contractor can be appointed as principal designer and principal contractor, which is common on fit-outs. That does not remove the client's own duties: you still have to make suitable arrangements, provide information and check that the plan and file exist. Where a client fails to appoint a principal designer or principal contractor on a project that needs them, the Regulations say the client must fulfil those roles.

Asbestos is the information most often missing

For refurbishment, the single most important piece of pre-construction information is usually the refurbishment and demolition asbestos survey of the areas to be disturbed. A management survey alone is not enough. HSE's HSG264 explains the difference. Commission it before the work is priced.

Notification is about size, not risk

A project is notifiable to HSE (using form F10) if 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. The client is responsible for notifying, though the principal designer or contractor often does it on the client's behalf. Most single-floor refurbishments with a sizeable team cross the 500 person-day line.

Occupied buildings need extra thought

When staff, pupils, patients or customers stay in the building, the client knows things the contractor does not: who is where and when, fire evacuation routes, deliveries, vulnerable people. Share that early and agree how the site will be separated from the occupied areas.

Building regulations dutyholders

Since October 2023, the Building Regulations in England also give clients, principal designers and principal contractors dutyholder and competence duties for building regulations compliance. They sit alongside CDM, with the same role names but a different purpose. Your contractor should be able to explain how both are covered.

Where our information comes from

Cost ranges are typical figures from published UK cost guides and price guides, read November 2026, given before VAT. Firms that publish them are not named.

A contractor used to CDM will tell you what they need from you on day one.

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How the work gets done

Where the client's CDM duties fall in a refurbishment.

  1. Before design

    Decide the budget and time, gather drawings and surveys, commission the asbestos survey, appoint a principal designer.

  2. Before tender

    Issue pre-construction information to everyone pricing, and check the competence of those you shortlist.

  3. Before work starts

    Appoint the principal contractor, see the construction phase plan, confirm welfare facilities, notify HSE if needed.

  4. At handover

    Receive the health and safety file, keep it with the building, and pass it on if you sell or let.

CDM questions

Do the CDM Regulations apply to small refurbishments?

Yes. CDM 2015 applies to all construction work. What changes with size is notification to HSE and how much paperwork is proportionate, not whether the duties exist.

When must a project be notified to HSE?

When construction work will last longer than 30 working days and have more than 20 workers on site at the same time at any point, or will exceed 500 person-days. Notification uses form F10.

What is a principal designer?

The designer appointed by the client to plan, manage and coordinate health and safety in the pre-construction phase, where more than one contractor is involved. They also prepare the health and safety file.

What is a principal contractor?

The contractor appointed to plan, manage and coordinate the construction phase where more than one contractor is involved, including the construction phase plan and site welfare.

What happens if we do not appoint them?

The client must carry out the principal designer and principal contractor duties itself. HSE can take enforcement action against clients who do not meet their duties.

Does CDM apply to schools and NHS buildings?

Yes, in the same way. The school, trust, local authority or NHS body commissioning the work is the client.

Keep reading

Brief a contractor who works to CDM

Three short steps: where the building is, what the scope is, and who to speak to. Rough answers are fine; a contractor firms them up on a site visit.

Your brief stays with us until you approve the independent commercial refurbishment contractor we name for your building.

Step 1 of 3

Where is the building?
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