CDM 2015 and Permit-to-Work Requirements: What Contractors Need to Know

The Construction (Design and Management) Regulations 2015 — usually called CDM 2015 — are the main set of regulations governing health and safety management on construction projects in the UK. If you work in construction, you are working under CDM whether you realise it or not. And if your projects involve high-risk activities, the CDM permit to work requirements affect how you plan, manage, and document that work.

CDM 2015 does not use the words "permit to work" very often. That catches people out. But the duties it creates — particularly for principal contractors — make a formal permit system either essential or very strongly implied for most projects of any complexity.

This guide explains how CDM 2015 connects to permit-to-work systems and what you need to have in place. If you need a refresher on what a permit system actually is, start with our plain-English guide to permit-to-work systems.

This guide provides general information about CDM 2015 as it relates to permit-to-work systems. It does not constitute legal advice. For project-specific CDM compliance, consult a competent health and safety professional.

How CDM 2015 Is Structured

CDM 2015 replaced the previous CDM 2007 regulations. The key change was extending duties to all construction projects, not just notifiable ones. There is no longer a project size threshold — even a small refurbishment with one contractor has CDM duties.

The regulations define five duty holder roles:

Client — the person or organisation commissioning the work
Principal designer — leads the pre-construction phase, managing design risks
Principal contractor — leads the construction phase, managing site safety
Designers — anyone who prepares designs (drawings, specifications, calculations)
Contractors — anyone carrying out or managing construction work

For permit-to-work purposes, the most relevant duty holders are the principal contractor and contractors.

Principal Contractor Duties That Drive CDM Permit to Work Requirements

The principal contractor's duties under CDM 2015 are set out in Regulations 12-14. Three regulations are directly relevant to permits:

Regulation 12: Construction phase plan

The principal contractor must draw up a construction phase plan before the construction phase begins. This plan must set out the arrangements for managing health and safety risks, including the specific controls for high-risk work.

HSE guidance (L153) — the Approved Code of Practice for CDM 2015 — makes clear that the construction phase plan should describe the permit-to-work arrangements where relevant. This means identifying which activities on the project will require permits, who will authorise them, and how the system will operate.

If your construction phase plan does not address permits for hot work, confined space entry, electrical isolation, working at height, or excavation near services, it has a gap that an HSE inspector is likely to notice.

Regulation 13: Duties of a principal contractor

Regulation 13(1) requires the principal contractor to "plan, manage, monitor and coordinate the construction phase" to ensure work is carried out safely. This includes:

Organising cooperation between contractors
Ensuring site rules are established and followed
Ensuring only authorised persons are allowed into areas where high-risk work is taking place

Permits are one of the primary mechanisms for all three of these. When a principal contractor issues site rules that say "no hot work without a permit," they are fulfilling their duty to establish rules. When the permit authorisation process requires the principal contractor's representative to sign off, they are coordinating and monitoring high-risk activities.

Regulation 14: Principal contractor's duty to consult and engage with workers

This regulation requires the principal contractor to engage with workers on health and safety matters. For permit systems, this means ensuring that the people doing the work understand the permit process, know how to complete the forms, and have the opportunity to raise concerns. A permit system imposed without consultation is less likely to be used properly.

What About Smaller Projects Without a Principal Contractor?

On projects with only one contractor, there is no principal contractor appointment. But the contractor still has duties under Regulation 15 to plan, manage, and monitor the work to ensure it is carried out safely. The client also has duties under Regulation 4 to make suitable arrangements for managing the project.

In practice, this means that even on a single-contractor project, if the work involves high-risk activities that warrant permits, the contractor needs a system in place. The HSE does not give you a pass on permit-to-work controls just because the project is small.

The Construction Phase Plan and Permits

The construction phase plan is the document where CDM permit to work requirements become concrete. For each high-risk activity, the plan should state:

Which activities require permits — be specific. "High-risk work" is too vague. List the permit types: hot work, confined space, electrical isolation, working at height, excavation.
Who can authorise permits — by role, not just by name (people change). For example: "Permits may only be authorised by the site manager or the deputy site manager."
What the permit process involves — reference your templates, describe the workflow from application through authorisation to close-out.
Where permit templates are held — whether in a physical permit book in the site office, a shared digital folder, or a permit-to-work platform.
How permits are monitored and audited — who checks that permits are being completed properly, how often, and what happens when problems are found.

If you are a subcontractor working under a principal contractor, you may be required to use the principal contractor's permit system rather than your own. This is common on larger sites. Check this during pre-start meetings to avoid duplication or confusion.

CDM 2015 and Documentation Requirements

CDM 2015 does not prescribe a specific permit format — paper or digital both satisfy the requirements. But the regulations place a strong emphasis on adequate documentation of safety arrangements, and permits are a key part of that documentation.

Two areas where documentation matters most:

Health and safety file

Regulation 12(5) requires the principal designer (and later the principal contractor) to prepare a health and safety file that contains information likely to be needed during future maintenance or construction. While individual permits do not typically go into the file, the permit-to-work procedures and any significant findings from permitted work (such as the discovery of asbestos during demolition, or unexpected ground conditions during excavation) should be recorded.

Evidence for inspection

HSE inspectors visiting a construction site will routinely ask to see the construction phase plan and any active or recent permits. They are looking for evidence that high-risk work is being properly controlled. A well-maintained permit register — whether a paper log or a digital dashboard — demonstrates this. Our guide to permit-to-work auditing covers what inspectors typically look for.

Practical Steps for CDM Compliance

If you are a principal contractor setting up or improving your permit system for CDM compliance:

Audit your current state. List the high-risk activities on your current or upcoming projects. Check whether you have a permit process for each one. Our free PTW readiness checker can help with this.
Update the construction phase plan. Make sure it explicitly addresses permit-to-work: which activities, who authorises, what templates, how they are stored and audited.
Choose appropriate templates. Use permit templates that cover the sections required by HSG250 — hazard identification, precautions checklist, dual signatures, close-out. Our permit to work template covers the standard structure, with specialist templates for hot work, confined spaces, working at height, electrical isolation, and excavation.
Define authorisation levels. Decide who can authorise each type of permit. Consider whether different permit types require different levels of competence — a confined space permit may need a more experienced authoriser than a general working-at-height permit.
Brief your subcontractors. Every contractor on site needs to understand the permit system before they start work. Include it in the site induction and reinforce it at pre-start briefings.
Audit regularly. Review completed permits at least monthly. Look for patterns: missing close-outs, incomplete checklists, permits issued after work has already started. These are the warning signs that the system is becoming a tick-box exercise. See our permit-to-work audit guide for a structured approach.

Key Legislation Referenced

Construction (Design and Management) Regulations 2015
HSE Approved Code of Practice L153 — Managing health and safety in construction
HSG250 — Guidance on permit-to-work systems
Management of Health and Safety at Work Regulations 1999

Summary

CDM 2015 does not mandate permits in so many words, but the duties it creates — planning, managing, monitoring, coordinating high-risk work — make a formal permit system the practical way to demonstrate compliance. The construction phase plan is where your permit arrangements should be documented. The principal contractor is responsible for ensuring the system works across all contractors on site.

If you are implementing a permit system to meet CDM requirements, our permit-to-work implementation guide covers the step-by-step process. PermitPad is building a digital permit-to-work system designed for UK contractors, with HSE-aligned templates and automatic audit trails. Join the waitlist to be notified when it launches.