In the UK, CDM 2015 applies to all construction projects, including domestic renovations, extensions, and commercial schemes. The legal duties of the client developer depend on the scale and complexity of the work, but the regulations apply whether you are building a single dwelling or managing a large-scale development.

Notifiable Projects Criteria

When acting as your Principal Designer we must notify the Health and Safety Executive (HSE) by submitting an an F10 notification if your project:

• Lasts more than 30 working days and has 20 or more workers on site at any time, or

• Involves more than 500 person-days of labour

Additionally if the project is Notifiable the client must:

• Appoint a Principal Designer (for pre-construction Health and Safety)

• Appoint a Principal Contractor (for on-site safety)

• Ensure a Construction Phase Plan is in place before work begins.

The Principal Designer is appointed by the client to take responsibility for Health and Safety during the pre-construction phase. Their role is to manage and coordinate health and safety risks in the design and planning of the project. At Paul Ashton Architects, we are fully qualified and experienced to act as your Principal Designer, ensuring that all duties under CDM 2015 are fulfilled efficiently and in line with best practice.

Our Principal Designer Services Include:

• Pre-Construction Risk Management
  We assess and manage foreseeable risks in the early stages, helping to eliminate or reduce them through considered design.

• Design Team Coordination
  We ensure all designers are aware of their duties and that health and safety is addressed across all aspects of the project.

• Communication with Contractors
  We liaise with the Principal Contractor and specialist consultants to ensure a smooth and safe handover from design to construction.

• Compilation of the Health and Safety File
  As required under CDM 2015, we prepare the Health and Safety File — a vital document that is handed to the client upon project completion. It includes:

  • As-built drawings

  • Specifications and product information

  • Maintenance and operational guidance

  • Notes on any residual risks

  This file must be kept and updated throughout the life of the building, forming part of your legal responsibilities as a property owner.

Failure to comply with CDM legislation can result in enforcement action, project delays, and serious legal liabilities. More importantly, CDM helps safeguard the health and wellbeing of everyone involved in the project — from consultants and contractors to future users of the building.

At Paul Ashton Architects, we integrate CDM compliance seamlessly into our design process, delivering not just architectural quality, but safe, legal, and buildable outcomes.

Work with Us

Whether you are a homeowner, developer, church organisation, or commercial client, we can act as Principal Designer and guide you through your legal obligations under CDM. Our health and safety-led approach ensures that your project progresses safely from concept to completion.

Contact Paul Ashton Architects today to discuss your project and CDM requirements.