For contractors

What is a construction phase plan?

Short answer

A construction phase plan is the document that records the health and safety arrangements for the construction phase, the site rules, and where relevant the specific measures for work in the categories listed in Schedule 3 of CDM 2015. It must be drawn up before a construction site is set up. On a project with more than one contractor the principal contractor draws it up; where there is only one contractor, that contractor does. It should be proportionate: detailed enough to set out the arrangements, short enough to be used.

What has to be in it

Regulation 12(2): the plan must set out the health and safety arrangements and site rules taking account, where necessary, of the industrial activities taking place on the construction site, and where relevant must include specific measures concerning work falling within one or more of the categories set out in Schedule 3.

HSE guidance expands that into the topics to consider:

A description of the project: key dates, and details of the key members of the project team.
The management of the work: the health and safety aims for the project, the site rules, the arrangements for cooperation between project team members and coordinating their work, arrangements for involving workers, site induction, welfare facilities, and fire and emergency procedures.
The control of any of the specific site risks listed in Schedule 3, where they are relevant to the work involved.

What to leave out

HSE guidance is unusually blunt here, and it is worth quoting the sense of it: the plan should not include documents that get in the way of a clear understanding of what is needed to manage the construction phase, such as generic risk assessments, records of how decisions were reached, or detailed safety method statements.

Why that matters commercially. A forty page plan assembled from a template is not a safer plan. It is a plan nobody on site will read, and the test in the guidance is whether the arrangements are clearly set out and communicated.

The Schedule 3 categories

Schedule 3 lists work involving particular risks. On small domestic projects most of it is irrelevant, and saying so is part of a proportionate plan.

Burial, engulfment or falls from height
Where the risk is aggravated by the nature of the work or process, or by the environment. This one does apply to ordinary building work.
Chemical or biological substances
Presenting a particular danger, or requiring health monitoring.
Ionising radiation
Requiring designated controlled or supervised areas.
Work near high voltage power lines
Risk of drowning
Wells, underground earthworks and tunnels
Divers with a system of air supply
Caissons with a compressed air atmosphere
Explosives
Assembly or dismantling of heavy prefabricated components
Which on a domestic job can mean the steelwork.

On a typical extension, one and ten are live and the rest are not. Asbestos, which is a real risk on that job, is dealt with under its own regulations rather than by Schedule 3.

Where the information comes from

Regulation 12(3) requires the principal designer to give the principal contractor everything they hold that is relevant to the plan, including the pre-construction information obtained from the client and the risk information obtained from designers. A contractor writing a plan without that is guessing at the parts of the job they cannot see.

Check a plan against the categories.

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