Principal Designers - What You Need to Know

CDM Principal Designer

A CDM Principal Designer is a key duty holder under the Construction (Design & Management) Regulations 2015. Their responsibility is to plan, manage and coordinate health and safety during the pre-construction (design) phase of a project.  What this looks like in practical terms is:

• Make sure risks are identified and eliminated or reduced as designs develop
• Work with architects, engineers and suppliers - acting as a central point of contact for project design
• Ensure that the safest materials, methods and layouts are considered throughout every stage of the design process
• Gathering pre-construction information to best understand project risks (e.g. existing structure, asbestos, ground conditions)
• Ensuring everyone on the project is aware of and understands the risks early
• Preparing the health and safety file, ensuring it is created and updated throughout the project. 

A CDM Principal Designer is required on all projects where more than one contractor is involved. The client is responsible for employing a CDM Principal Designer. 

Building Regulations Principal Designer

A Building Regulations Principal Designer (BRPD) is a duty holder under the recent Building Safety Act (2022) and detailed in the Building Regulations etc. (Amendment) (England) Regulations 2023. 

Their role is to plan, manage and monitor design work to ensure compliance with Building Regulations. This goes beyond health and safety and is focused on legal compliance of construction projects. Key responsibilities of this role include:

• Ensuring designs meet all relevant parts of Building Regulations - structure, fire safety, energy performance and accessibility. 
• Reviewing designs against regulatory requirements
• Overseeing the design process and ensuring proper checks and approvals are in place. 
• Ensuring everyone on site - from designers to installers - is competent in their role, and can prove it.

A Building Regulations Principal Designer is required on all projects where Building Regulations apply (which is most of the time). 

Do you need different people in each role?

The short answer is no. The same person can be appointed as CDM Principal Designer and Building Regulations Principal Designer IF they are fully competent in both roles. They must be able to demonstrate their competence in health and safety in the design process alongside their technical knowledge of building regulations. 

Who is the regulatory authority for CPS scheme work?

Most CPS registered contractors will be working on buildings under 18M. This type of work is regulated by Local Authority Building Control, and relevant works can be self-certified through the Competent Person Scheme. 

Buildings above 7 storeys or 18m are classed as High Risk Buildings and these are overseen by the Building Safety Regulator, and the Gateway principle applies:

• Gateway 1 (planning stage)
• Gateway 2 (pre-construction)
• Gateway 3 (post-construction; pre-occupation)

What clients should watch out for when hiring Principal Designers

If a Principal Designer does not know which regulatory body is responsible for the type of work they’re doing, it signals a fundamental gap in their understanding, and suitability for the role. We often see the wrong type of designer appointed to the role; for example Building Regulations Principal Designer without appropriate knowledge of HRBs. 

On Higher Risk Buildings it might be beneficial to separate these roles, and clients often recruit separate CDM Principal Designers and Building Regulations Principal Designers on complex and/or high-risk projects. 

Competence of your CDM and Building Regulations Principal Designers should be assessed for each project. They should be able to demonstrate the SKEB (skills, knowledge, experience and behaviours) associated with each role.