Construction regulations FAQs

The CDM Regulations 2015 are the Construction (Design and Management) Regulations 2015, which set out the legal framework for managing health, safety, and welfare on construction projects in the UK.

They place clear duties on:

• Clients
• Designers
• Principal designers
• Principal contractors
• Contractors

The regulations apply to all construction work, including domestic projects, and aim to reduce risk by improving planning, coordination, and communication throughout a project.

For more information, please read our article, What are the CDM Regulations?

The main aim of the Construction (Design and Management) Regulations 2015 is to reduce the risk of death, injury, and ill health on construction projects by ensuring that health and safety is properly planned, managed, and coordinated at every stage of a project — from design through to completion.

The CDM Regulations apply to all construction work in the UK, from the very start of a project (planning and design) through to completion and handover.

The Construction (Design and Management) Regulations 2015 apply to:

• All construction projects, regardless of size or duration
• Commercial and domestic projects
• All stages of work, including design, preparation, building, alteration, maintenance, and demolition

Additional duties apply where projects are notifiable (for example, if they last more than 30 working days with 20 workers on site at the same time, or exceed 500 person-days)

Yes, the CDM Regulations are statutory.

The Construction (Design and Management) Regulations 2015 are legal requirements, not guidance. This means they must be complied with by law, and failure to do so can result in enforcement action, fines, or prosecution by the regulator.

Yes. The Construction (Design and Management) Regulations 2015 apply to all construction projects in the UK, regardless of size, duration, or whether the work is commercial or domestic.

The level of duty varies depending on the project, but every project must comply with CDM in some form.

Yes. The Construction (Design and Management) Regulations 2015 do apply to domestic properties.

For domestic projects, most client duties are automatically passed to the contractor or principal contractor, and to the principal designer where one is appointed. This ensures health and safety is still properly managed, even for household building work.

Part 4 of the Construction (Design and Management) Regulations 2015 identifies the health and safety requirements for construction sites.

It sets out the minimum standards that must be in place on site, including:

• Safe access and movement
• Fire safety and emergency procedures
• Welfare facilities (toilets, washing, rest areas)
• Stability of structures
• Protection from falling, falling objects, and dangerous substances

In short, Part 4 defines how construction sites must be set up and run safely.

Under the Construction (Design and Management) Regulations 2015, a construction project is notifiable to the HSE if it:

• Lasts more than 30 working days and has more than 20 workers on site at the same time, or
• Exceeds 500 person-days of construction work in total

Notifiable projects require the client to ensure the HSE is notified and that a principal designer and principal contractor are formally appointed.

Responsibility for the Construction (Design and Management) Regulations 2015 is shared between all key duty holders on a construction project. These are:

• The client – has overall responsibility for ensuring health and safety is properly managed.
• The principal designer – manages health and safety during the design phase.
• The principal contractor – manages health and safety during the construction phase.
• Designers – must eliminate or reduce risks through design.
• Contractors – must plan and carry out work safely.
• Workers – must follow site rules and work safely.

Each party is legally responsible for their own duties under CDM.

A CDM risk assessment is a structured assessment used to identify, evaluate, and control health and safety risks on a construction project in line with the Construction (Design and Management) Regulations 2015.

It focuses on:

• Hazards specific to construction activities
• Risks arising from design, sequencing, and methods of work
• Measures to eliminate, reduce, or control risks before and during construction

It supports safer planning, coordination between duty holders, and compliance with legal duties under CDM.

In the UK, construction companies are regulated by the Health and Safety Executive (HSE).

The HSE is responsible for:

• Enforcing health and safety law on construction sites
• Inspecting sites and investigating accidents
• Taking enforcement action, including prosecutions where needed

Local authorities may also regulate smaller construction projects and certain types of premises, but the HSE is the main national regulator for the construction industry.

Failing to appoint a Principal Designer when required under the CDM Regulations 2015 is a breach of the law and may result in enforcement action by the Health and Safety Executive (HSE). This can include fines, project delays, or even prosecution.

Without a Principal Designer, there is a higher risk of poor planning, unmanaged hazards, and non-compliance, which can jeopardise the safety of workers and others involved in the project.

The responsibility for appointing a Principal Designer lies with the client.

Regulation 7 of the CDM Regulations 2015 ensures that anyone appointed as a duty holder, such as a designer, contractor, or Principal Designer/Principal Contractor, has the necessary skills, knowledge, and experience to carry out their role safely and effectively.

For organisations, it also requires the appropriate organisational capability to manage health and safety risks.

This regulation is designed to prevent the appointment of incompetent parties, thereby reducing risks and ensuring project safety and compliance.

The general duties under the CDM Regulations 2015 require all duty holders (clients, designers, contractors, Principal Designers, and Principal Contractors) to ensure health and safety throughout a construction project. This includes identifying and managing risks, ensuring proper planning and communication, and providing adequate resources for safety.

Duty holders must also ensure that those they appoint are competent and that workers are trained and informed about health and safety risks and procedures.

Under CDM 2015, every construction project (not just notifiable ones) must have these three core documents:

1. Pre-Construction Information (PCI)
   Information provided before work starts to help designers and contractors plan safely.
2. Construction Phase Plan (CPP)
   A live plan setting out how health and safety risks will be managed during construction. This is required before work begins, even for small or short-duration jobs.
3. Health and Safety File
   A record of key safety information for future use, maintenance, alteration, or demolition of the building.

These documents form the minimum paperwork the HSE expects to see to demonstrate CDM compliance.

A Construction Phase Plan (CPP) is legally required for all construction projects, including small, short-duration, and domestic jobs.

For minor works, the CPP does can be a simple, proportionate document, sometimes just one page, setting out:

• the work being done,
• the main health and safety risks, and
• how those risks will be controlled.

Work must not start until a CPP is in place, regardless of project size, under CDM 2015.

A CDM Principal Designer is appointed under CDM 2015 and is responsible for managing health and safety risks during design, specifically to prevent injury or ill health during construction, use, maintenance, and demolition.

A Building Safety Act (BSA) Principal Designer is appointed under the Building Safety Act 2022 / amended Building Regulations and is responsible for ensuring design compliance with the Building Regulations, particularly fire and structural safety.

The same person often performs both roles, but they must be formally appointed and able to demonstrate competence for each role separately.

The Golden Thread of information is a digital, accurate, and up-to-date record of building safety information required under the Building Safety Act 2022.

It ensures that key safety decisions and details are:

• created, stored, and updated digitally,
• kept throughout a building’s lifecycle (design, construction, and occupation), and
• accessible to those responsible for managing safety.

For higher-risk buildings, maintaining the Golden Thread is a legal requirement, and failure to do so can lead to enforcement action by the Building Safety Regulator.

If a client fails to appoint a Principal Designer or Principal Contractor, the legal duties still apply.

Under CDM 2015, those duties default to the client. The client therefore becomes legally responsible for carrying out the functions of the Principal Designer and/or Principal Contractor, including:

• planning, managing, and coordinating health and safety, and
• ensuring risks are properly identified and controlled.

In effect, the client assumes full legal responsibility for those roles if they are not formally appointed.

To prove skills, knowledge, and experience (competence) under CDM 2015 and the Building Safety Act 2022, you must be able to show relevant, current, and role-specific evidence.

In practice, this means demonstrating:

• Appropriate qualifications and training relevant to the role (e.g. construction, design, fire or structural safety)
• Relevant experience on similar types and scales of project
• Up-to-date CPD covering current health and safety law and building safety requirements
• Professional body membership where appropriate (e.g. RIBA, ICE, CIOB, IOSH)
• Evidence of capability, such as previous project records, safety documentation, or compliance audits

For higher-risk buildings, competence must be documented and demonstrable, not assumed. Regulators expect clear, auditable evidence, not just job titles or CVs.

A Fee for Intervention (FFI) is a charge made by the Health and Safety Executive when it identifies a material breach of health and safety law.

If the HSE finds a breach during an inspection, it can recover the cost of its time spent investigating, taking enforcement action, and writing up the case. The fee is charged per hour and applies in addition to any fines or other penalties.

Under CDM 2015, directors and senior managers can face personal legal consequences where construction health and safety duties are breached.

If a CDM offence is committed with a director’s consent, connivance, or neglect, they can be prosecuted personally under Section 37 of the Health and Safety at Work etc. Act 1974.

This can result in:

• personal criminal charges,
• unlimited fines, and
• imprisonment for up to 2 years in serious cases.

Directors must be able to demonstrate active oversight, proper appointments, and adequate resourcing of CDM duties. Delegating responsibilities does not remove personal liability.