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Compliance Guide

How to Write a Construction Phase Plan (CDM 2015)

A practical guide for UK site managers, principal contractors and small builders.

Under CDM 2015 every construction project needs a construction phase plan before work starts on site. On a domestic loft or a large commercial fit out, the duty is the same. Get it right and it sets the tone for a safe, well run job. Get it wrong and you are exposed the moment an inspector or client asks to see it. Here is what a good plan covers and how to write one that reflects the actual work.

What a construction phase plan is and when you need one

The construction phase plan sets out the health and safety arrangements, site rules and specific measures for the building work. CDM 2015 requires one for every project, however small. On single contractor jobs the contractor prepares it. Where there is more than one contractor, the principal contractor draws it up before the construction phase begins.

Start with the project, not a template you found online

A generic plan with the name swapped over convinces nobody and protects nobody. Describe this project: what is being built, the site, access, the programme, the contractors involved and the client. The plan should read as if it was written for this job, because it was.

Set out the health and safety arrangements

Explain how the work will be managed. Roles and responsibilities, site induction, welfare facilities, how you will consult the workforce, emergency procedures and first aid, and how the site is kept secure. This is the section that shows you have thought about running the site, not just filling in a form.

Cover the significant risks and the controls

List the significant health and safety risks for this project and what you are doing about each one. Working at height, excavations, services, deliveries and traffic, dust, manual handling, and any work needing a permit. Tie each risk to a clear control measure so the people on the tools know exactly what is expected.

Keep it live for the whole build

The plan is not a document you write once and file away. Review and update it as the work moves through its phases and as new contractors and risks come on site. Toolbox talks, inductions, inspections and the plan itself should sit together against the project, not scattered across phones and the van.

A useful rule of thumb: the construction phase plan is about how the whole project is managed safely from start to finish. A RAMS covers a single task in detail. You will usually need both, and they should agree with each other rather than contradict.

Frequently asked questions

Do I need a construction phase plan for a small domestic job?

Yes. CDM 2015 requires a construction phase plan for every construction project, including domestic work. It can be short and proportionate to a small job, but it still has to exist before work starts.

Who is responsible for writing it?

On a single contractor project the contractor prepares the plan. Where more than one contractor is involved, the principal contractor prepares it and keeps it up to date through the construction phase.

What is the difference between a construction phase plan and a RAMS?

The construction phase plan covers how the whole project is managed safely. A risk assessment and method statement covers the hazards and safe method for a specific task. The plan sits above the individual RAMS and pulls the site level arrangements together.

The shortcut

Writing a proper construction phase plan for every job is the part that costs you evenings. Site Manager AI produces a project specific construction phase plan, RAMS, method statement and toolbox talk in minutes, scoped to UK regulations, and answers your CDM and Building Regs questions on the spot. You get compliant, professional documents and your evenings back.

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This article is general guidance for UK construction and is not legal advice. For requirements specific to your work, check current HSE guidance and your own duty holder obligations under CDM 2015.