Yes. CDM 2015 applies to all construction work. There is no size, value or duration below which it stops applying. What changes as a job gets bigger is notification, the appointments and the health and safety file, not whether the regulations apply.
"It's only a small job. CDM doesn't apply to us." It is one of the most common things we hear, and there is nothing in the regulations to support it. If somebody tells you a project is too small for CDM, ask them which regulation says so.
What applies to every project
Client duties. Regulation 4 requires a commercial client to make suitable arrangements for managing the project, including sufficient time and resources, and to keep them under review. The size of the job changes how much that involves, not whether it applies.
Pre-construction information. The client must provide it, as soon as is practicable, to every designer and contractor appointed or being considered (regulation 4(4)).
A construction phase plan. Regulation 4(5) requires the client to make sure one is drawn up before the construction phase begins. On a single contractor job, regulation 15(5) puts that on the contractor.
Welfare. Suitable arrangements include providing the welfare facilities set out in Schedule 2 (regulation 4(2)).
The site rules. Part 4 of CDM 2015 (regulations 16 to 35) applies to every construction site, whatever its size.
What changes as a job gets bigger
More than one contractor. Once more than one contractor is working, or that is reasonably foreseeable, the client must appoint a principal designer and a principal contractor in writing (regulation 5(1)). The health and safety file is only required on these projects.
The notification thresholds. A project must be notified to HSE with an F10 if it is scheduled to last longer than 30 working days with more than 20 workers on site at the same time, or to exceed 500 person days (regulation 6(1)). Our free F10 checker works it out in a minute.
Notification is the threshold people remember, and it is the reason the myth persists. But it is the only part of CDM 2015 with a size test, and it decides whether HSE is told about the project, not whether the duties apply.
Proportionate is not the same as optional
HSE's guidance says the actions people take under CDM 2015 should always be proportionate to the risks in the project. That is the honest answer to "surely a two-day job doesn't need all this": it needs the same things, in proportion.
A construction phase plan for a three-day redecoration can be a short document. HSE publishes short guidance for busy builders, with a template (CIS80). What it cannot be is absent.
Two worked examples
A three-day redecoration by one firm. One contractor, so no principal designer or principal contractor, and no health and safety file. The client still needs suitable arrangements and must pass on what they know about the building, such as any asbestos information. The contractor draws up a short construction phase plan before starting, and welfare is provided.
A one-week office refit with a joiner and an electrician. Two contractors, so the client must appoint a principal designer and a principal contractor in writing, before the construction phase begins. There will be a construction phase plan and a health and safety file. The job is far below the notification thresholds, so no F10, but every other duty applies in full.
Common questions
Is a construction phase plan needed for a one-day job?
Yes. The regulations require one before the construction phase begins, on every project. For a short, low-risk job it can be brief.
Does maintenance count?
Yes. The definition of construction work includes repair, upkeep, redecoration and other maintenance. See planned preventative maintenance and CDM 2015.
What about work on someone's own home?
CDM 2015 still applies, but the client duties pass to the contractor or the principal designer. See domestic clients under CDM 2015.
For the client's side in full, see what Regulation 4's suitable arrangements mean. Our free one-page checklists cover the programme, the site gate and handover.
This article is general information, not legal advice.