CDM Duty-Holder Checker

The Construction (Design and Management) Regulations 2015 require specific duty holders to be in place depending on the project. This tool identifies who is required and whether formal written appointments are needed.

Three questions. Under a minute. No login required.

Is the client domestic or commercial?

A domestic client is someone who has construction work carried out on their own home (or the home of a family member). All other clients are commercial — including housing developers, landlords, and businesses.

Frequently asked questions

What are CDM 2015 duty holders?
CDM 2015 defines five duty-holder roles: client, principal designer, principal contractor, designer, and contractor. Each carries specific legal responsibilities for managing health and safety risks during design and construction. The roles required depend on the project structure — particularly how many contractors are involved.
When do I need a principal designer and principal contractor?
A principal designer and principal contractor must be appointed on any project with more than one contractor (including subcontractors). On single-contractor projects, the contractor takes on the duties that would otherwise fall to the principal contractor, and the designer takes on principal designer duties.
Who appoints the CDM duty holders?
The client is responsible for making all CDM appointments. On multi-contractor projects, the client must appoint the principal designer and principal contractor in writing before the construction phase begins. The client must ensure that appointees have the skills, knowledge, experience, and organisational capability to carry out their roles.
Do domestic clients have CDM duties?
Yes, but domestic clients (people having work done on their own home) are treated differently. Their duties automatically pass to the contractor on single-contractor projects, or to the principal contractor on multi-contractor projects, unless the domestic client appoints a principal designer — in which case that appointment triggers the full duty-holder structure.

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