ClearCDM

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Do I need a CDM principal designer?

Six questions, a plain answer, and the reasoning shown. Nothing to buy and no email address needed.

Is somebody doing this work for you?

The first fork in HSE's own decision chart for domestic clients.

This tool gives general guidance from the answers you type. It is not legal advice about your project, and it cannot see your drawings or your site. Where a project is unusual the answer is a conversation rather than a checker. How we write this.

What this checker is doing

It walks the same sequence the regulations do, in the order they apply.

  1. Is it construction work carried out on your behalf?

    If you are doing it yourself on your own home, HSE's decision chart treats it as DIY and CDM 2015 does not apply.

  2. Domestic client or not?

    This decides whether regulation 7 reallocates the client duties, and what happens if nobody is appointed.

  3. More than one contractor?

    The single trigger in regulation 5(1). Subcontractors count and do not have to overlap.

  4. Has an appointment been made in writing?

    If yes, regulation 5 is satisfied. If no, regulation 5(3) or regulation 7(2) decides where the duties have already gone.

  5. Who controls the design?

    On a domestic project with no appointment, regulation 7(2) puts the role on the designer in control of the pre-construction phase.

  6. Has work started?

    Does not change whether the appointment is required. It changes how much of the role is still recoverable.

Domestic client appoints nobodyThe designer in control ofthe pre construction phaseThe contractor in control ofthe construction phaseis the principal designeris the principal contractorCarries regulation 11and 12 dutiesCarries regulation 12 to 14duties, and the client's
What regulation 7(2) of CDM 2015 does when a domestic client makes no appointment. The role does not disappear. The designer in control of the pre construction phase is the principal designer, and the contractor in control of the construction phase is the principal contractor. On top of that, regulation 7(1) moves the domestic client's own duties onto the principal contractor unless the principal designer has agreed in writing to carry them.

Written by Robbie Thompson, BA (Hons) Dip Arch, SMSTSLast reviewed 28 August 2026How we write this

Related questions

Sources

  1. CDM 2015, regulation 5 legislation.gov.uk
  2. CDM 2015, regulation 7 legislation.gov.uk
  3. CDM 2015, regulation 15 legislation.gov.uk
  4. Managing health and safety in construction, L153, Appendix 6 HSE guidance