Construction phase plan: who writes it, and when is it required?

Yes, and this is the most common misunderstanding about CDM 2015. Three separate thresholds get confused with each other, and only one of them has anything to do with the plan.

Notification and the plan are different tests. A job can be far too small to notify and still require a construction phase plan, because every job does.

For domestic clients the duties do not disappear, they transfer: the client’s duties pass to the contractor, or to the principal contractor where there is more than one. See when CDM applies and what the F10 is for.

CDM 2015 does not prescribe a format. It requires the plan to set out the arrangements for the project and the site rules, taking account of the risks involved. In practice an inspector expects to find five things.

1. 01Project description. What is being built, where, the programme, and who holds each duty holder role with contact details.
2. 02Management arrangements. Who is responsible for what; how the work is supervised; how workers are inducted, consulted and briefed; how contractors are appointed and checked.
3. 03Site rules. The things that apply to everybody on site: PPE, permits, access, deliveries, restricted areas, speed limits.
4. 04Arrangements for controlling significant risks. The specific ones for this site, not a list of every hazard in construction. Work at height, excavations, services, lifting, asbestos, confined spaces, whichever actually apply here.
5. 05Emergency arrangements. Fire, first aid, evacuation, assembly point, nearest hospital, and who raises the alarm.

NoteThe plan is not a risk assessment and does not replace one. Risk assessments and method statements sit underneath it and are referenced by it. See what a RAMS must contain.

Because the regulation asks for arrangements "taking account of the risks involved" on that project, and a template accounts for the risks of no project at all. The tell is usually visible in seconds.

• Risks that are not on the site. A confined-space section on a loft conversion says nobody read it.
• Risks that are on the site and not in the plan. The scaffold, the live services, the asbestos survey nobody has actioned.
• Names and numbers that are wrong. A first aider who left, a principal designer who was never appointed.
• No dates or revisions. A plan written once and never touched, on a job whose risks changed twice.
• Nothing about how workers are briefed. The plan can be perfect and worth nothing if the people on site have not seen it.

The proportionality point cuts both ways. A small job does not need a fifty-page document, a short, specific plan is better than a long generic one. But it does need to exist, and it does need to be about this site.

They are different documents at different ends of the job, and mixing them up is common.

The plan is live for the duration of the works and should be revised when the work changes. The file is assembled during the project and handed over at practical completion.

Regulation 12 is a legal duty, and the absence of a plan is one of the first things an HSE inspector asks for on an unannounced visit. It is also frequently the finding that follows an accident, because the investigation asks what the arrangements were and the answer has to be a document that predates the incident.

The commercial consequence usually arrives sooner than the regulatory one. Principal contractors ask for the plan at pre-qualification; so do most insurers, and so does anyone operating a PAS 91 or common assessment standard process. A contractor who cannot produce one for the last three jobs will struggle to be appointed on the next.

It has to exist before the construction phase begins. A plan written after an incident, or after an inspector asks, is not evidence of arrangements, it is evidence there were none.