Principal designer appointments under CDM 2015 and the Building Regulations 2010 (as amended) — pre-construction information, design risk management and compliance.
Most clients discover the principal designer requirement late — usually when a contractor or building control asks who holds the appointment. The law is straightforward: on any project involving more than one contractor, CDM 2015 requires the client to appoint a principal designer in writing for the pre-construction phase; and since the Building Safety Act reforms, a separate principal designer duty exists under the Building Regulations for building control compliance. Fail to appoint, and the duties — and the liability — default to you as the client.
What the appointment covers
- CDM 2015 principal designer — planning, managing and monitoring health and safety in the pre-construction phase: pre-construction information, design risk reviews, co-ordination between designers, and the health and safety file at handover.
- Building Regulations principal designer — the compliance-focused role introduced in 2023: taking reasonable steps to ensure the design, if built, complies with building regulations.
- Client duty advice — F10 notification where required, competence checks on your design team and contractors, and keeping the paperwork inspection-ready.
Why appoint a surveyor
The role rewards a professional who understands buildings, buildability and regulation at once — which is building surveying's home ground. Appointing the principal designer alongside our project management or contract administration service means one team carries the design intent, the compliance duty and the site inspections, with nothing lost between separate firms.
Fees and instruction
Fixed fees scaled to project size and design complexity, agreed before appointment. Domestic clients: on most home projects the duty passes to the contractor or lead designer by default — we will tell you honestly whether you need a separate appointment at all.
Frequently asked questions
Is a principal designer a legal requirement?
Yes, in defined circumstances. Under CDM 2015, any project with more than one contractor requires the client to appoint a principal designer in writing for the pre-construction phase — and if you don't appoint one, the duties (and liability) rest with you as client. Since 2023 there is also a separate principal designer duty under the Building Regulations for building control compliance on notifiable work.
What is the difference between the CDM and Building Regulations principal designer?
Two distinct legal roles that happen to share a name. The CDM 2015 principal designer manages health and safety risk in the pre-construction phase. The Building Regulations principal designer — introduced by the Building Safety Act reforms — must take reasonable steps to ensure the design complies with building regulations. One competent professional can, and usually should, hold both appointments.
Do domestic projects need a principal designer?
The duties still apply, but for domestic clients they transfer automatically — normally to the contractor (or principal contractor), or to the lead designer where there is a written agreement. So most homeowners need not appoint separately. On complex projects — basements, structural remodelling, multiple contractors — a deliberate appointment is still worth making, and we will tell you honestly if yours doesn't need one.