Someone has to be responsible for safety on your project. On ours, it is us.
Every building project in England has a Principal Designer by law, including a rear extension or a loft. Most homeowners never hear the term because the role is quietly left to whoever turns up. Paradigm takes it on as part of our appointment, so the people who designed your house are also the people answerable for how safely it is designed and built.
Two roles with the same name.
1. Safety: CDM 2015
The Construction (Design and Management) Regulations 2015 apply to all construction work, including work on your own home. Whenever more than one contractor will be involved (a builder plus an electrician already counts), the client must appoint a Principal Designer and a Principal Contractor in writing.
The Principal Designer plans, manages and coordinates health and safety through the design stage: identifying risks that can be designed out, briefing the people who will build it, and preparing the health and safety file you keep when the work is finished.
2. Compliance: Building Regulations
Since 1 October 2023 the Building Regulations have their own dutyholder roles, introduced by the Building Safety Act 2022. The Building Regulations Principal Designer is responsible for planning, managing and monitoring the design so that, if built as drawn, the work complies with the regulations: structure, fire, insulation, ventilation, drainage and the rest.
At completion the Principal Designer and Principal Contractor each sign a compliance declaration that goes to Building Control. It is a different role from the CDM one, and on a Paradigm project the same team holds both.
What it means if you own the home
Homeowners are "domestic clients" under both sets of regulations. You are not expected to manage any of this yourself. By default your client duties pass automatically to the contractor, or to the Principal Contractor where there is more than one.
Under CDM you can instead choose, in a written agreement, for the Principal Designer to carry your client duties. We offer that agreement as standard, so one firm holds the thread from first sketch to handover.
The work behind the title.
- 01Design risk, designed outWe look at how the building will be built, cleaned and maintained while it is still on paper: where the steel goes in, how the roof is accessed, what happens to the party wall. Risks that can be removed by design are.
- 02Pre-construction informationEverything a builder needs to price and plan the work safely, in one pack: surveys, asbestos and services information, the structural design, the sequence we expect, and the constraints of your site and your neighbours.
- 03CoordinationOur architects and structural engineers are one team, so the coordination the role demands happens around one desk. Where a specialist joins, such as a party wall surveyor or a mechanical engineer, we brief them and check their work against the rest.
- 04Building Regulations complianceWe plan the design to comply, check it as it develops, and liaise with Building Control, whether the local authority or an approved inspector. Where we are also main contractor, we sign both compliance declarations at completion.
- 05The health and safety fileAt handover you receive the file: what was built, where the structure and services are, and what the next owner or builder needs to know. Keep it with the deeds.
What homeowners ask us.
Does a small extension really need all this?
Yes. CDM 2015 applies to every construction project in Great Britain. The duties scale with the risk, so a single-storey extension needs a proportionate approach rather than a thick file, but the roles still exist and someone still holds them. A project is also notifiable to the HSE if it will last more than 30 working days with more than 20 workers on site at once, or exceed 500 person-days; most domestic projects fall below that, which is why most homeowners never hear about it.
What happens if nobody is appointed?
For a domestic client the duties default to the contractor in control of the work. That can be fine with a good builder, but it means the person checking the design for safety and compliance is the person being paid to build it, with no one else looking.
Is this the same as Building Control?
No. Building Control (the council or an approved inspector) checks and certifies the work. The Principal Designer is on your side of the table, responsible for the design being compliant before it is checked and for coordinating everyone who contributes to it.
Is the Principal Designer the same as the Principal Contractor?
They are two roles. The Principal Designer manages the design stage; the Principal Contractor manages the site. They can be held by different firms, which is what happens when we tender your project to a builder. On projects where Paradigm is appointed as main contractor, we hold both, under one agreement with you. Building with Paradigm
What does it cost?
On projects where Paradigm leads the design, the Principal Designer role is part of our appointment rather than a separate fee. Where you already have a design and need a Principal Designer only, ask us: it depends on the project.