Under the Construction (Design and Management) Regulations 2015, a homeowner who commissions building work on their own home is a domestic client, and the client duties normally pass to the contractor on a single-contractor job or to the principal contractor where there are several.

Who is a domestic client

HSE says a domestic client is any individual who has construction work carried out on their home, or the home of a family member, that is not done as part of a business. A client who has construction work carried out in connection with a business is a commercial client. HSE notes that many domestic clients have little or no skill in managing a construction project, which is why CDM 2015 passes their duties to other dutyholders. The Construction (Design and Management) Regulations 2015, known as CDM 2015, apply in Great Britain and place the full client duties on commercial clients.

Where the duties go

Regulation 7 says that where the client is a domestic client, the duties in regulations 4(1) to (7) and 6 must be carried out by the contractor for a project with only one contractor, by the principal contractor for a project with more than one contractor, or by the principal designer where there is a written agreement that the principal designer will do so. HSE says that on a single contractor project the contractor takes on the client’s legal duties on top of their own, which in practice should involve little more than what they normally do to manage health and safety risks.

On a project with more than one contractor, a domestic client who has engaged an architect or other designer can agree in writing that the designer manages the project and takes on the client duties, becoming principal designer. Without that written agreement, HSE says the client duties automatically pass to the principal contractor. If the domestic client fails to make the required appointments, regulation 7(2) makes the designer in control of the pre-construction phase the principal designer and the contractor in control of the construction phase the principal contractor.

What a homeowner still needs to do

HSE stresses that a domestic client does not need skills or experience in managing construction. Provided reasonable enquiries are made of those brought in about their awareness of health and safety risks and their track record in managing them, the client should be able to rely on them. It suggests asking simple questions about track record and allowing enough time and money in the contract for the work to be done safely.

What a contractor must be able to show

HSE says a contractor must be able to demonstrate the skills, knowledge and experience, and for an organisation the organisational capability, to carry out the work safely, and that the level should be proportionate to the complexity of the work and the risks. It gives examples of evidence: records of continuing professional development and training, membership of professional bodies and references from earlier construction work. A contractor that employs others must ensure those individuals are suitably skilled and trained or in the process of becoming so.

Planning, the construction phase plan and paperwork

HSE says details of a contractor’s planning must be recorded as a construction phase plan and that the effort should be proportionate to the project. Under regulation 12, the principal contractor draws up the plan before the site is set up and keeps it under review. The principal designer prepares a health and safety file during the pre-construction phase and, at the end of the project, passes it to the client, or the principal contractor does so where there is no principal designer.

HSE’s notification page adds that where a project is notifiable to HSE and the client is domestic, the notification is made by the contractor or principal contractor, or by the principal designer under a written agreement, and that for a single contractor project the contractor’s name is entered in both roles. The form requires the contact details of the client, principal designer and principal contractor.

FAQs

Is a homeowner responsible for site safety on a conservatory build?

HSE says a domestic client’s duties normally pass to the contractor or principal contractor, although the client should still check the contractor is capable.

Does the homeowner need a construction phase plan?

No. HSE says the contractor records planning as a construction phase plan, and under regulation 12 the principal contractor draws it up where there is more than one contractor.

Does this apply in Northern Ireland?

HSE’s guidance covers Great Britain. Northern Ireland has separate health and safety regulation.

Bottom line

For most conservatory projects, the homeowner is a domestic client whose CDM duties pass to the contractor, but the homeowner can still make sensible enquiries about the contractor’s capability and allow enough time and money for safe working. Regulation 7 sets out where the duties go, and the contractor or principal contractor produces the plan. This is general information, not legal advice; HSE and the contractor can explain how the rules apply to a specific job.

Sources

This guide draws on the following primary sources, current as of 21 September 2026:

• Health and Safety Executive, “Domestic clients: roles and responsibilities”
• Health and Safety Executive, “Are you a domestic client?”
• Health and Safety Executive, “Are you a contractor?”
• Health and Safety Executive, “F10 – Notification of construction project”
• legislation.gov.uk, “The Construction (Design and Management) Regulations 2015, regulation 7: Application to domestic clients”
• legislation.gov.uk, “The Construction (Design and Management) Regulations 2015, regulation 12: Construction phase plan and health and safety file”

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Compare Conservatories is an independent guide. We may earn a fee from some links; this never affects what we write. This article is general information, not legal or planning advice on any specific property — always confirm requirements directly with your local planning authority.