Episode 207 - Under D&B who is responsible for specialist design compliance

This week we are going to discuss a deceptively simple question with big consequences: under the Building Safety Act and the new Building Regulations dutyholder regime, when the Principal Contractor is in place, who is actually responsible for specialist design compliance. This episode content meets PC2 - Clients, Users & Delivery of Services & PC3 - Legal Framework & Processes of the Part 3 Criteria.

Resources from today's episode:

Website:

• https://www.riba.org/work/insights-and-resources/professional-features/building-safety-act-professional-features/building-safety-act-under-the-principal-contractor-who-is-responsible-for-specialist-design-compliance/
  
  

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Transcript

Episode 207:

Hello and Welcome to the Part3 with me podcast. 

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I am your host Maria Skoutari and this week we are going to discuss a deceptively simple question with big consequences: under the Building Safety Act and the new Building Regulations dutyholder regime, when the Principal Contractor is in place, who is actually responsible for specialist design compliance. Todays’ episode meets PC 2 & 3 of the Part 3 Criteria.

And make sure to stay until the end for today’s scenario. 

The Building Safety Act has reshaped the way we think about design responsibility, adding new statutory dutyholders, Principal Designer and Principal Contractor under the Building Regulations, alongside familiar contractual roles like lead designer, design‑and‑build contractor, and specialist subcontractors.

So in today’s episode we will expand on a very focused question: “Under the Principal Contractor, who is responsible for specialist design compliance?” In other words, once the main contractor is on board and the specialist packages kick in, like cladding, MEP, fire systems, lifts and so on, who carries the responsibility for ensuring that design work complies with the Building Regulations?

We’ll look at:

• How the new dutyholder regime works in relation to design and specialist designers.
• What happens on a typical design and build project when the Principal Contractor takes on design control.
• How responsibilities are split between Principal Designer, Principal Contractor and individual specialist designers.

So starting with the dutyholder framework: who does what under the new regime:

We touched on these in previous epiosde but let’s set the scene by briefly setting the framework, under the Building Regulations as amended by the Building Safety Act, the key statutory dutyholders are the Client, Principal Designer, Designers, Principal Contractor and Contractors.

The Client must appoint a Principal Designer and a Principal Contractor in writing for almost all projects and if they fail to do so, they effectively take on those duties themselves (excluding domestic clients, who are treated differently).

As you know, the Principal Designer’s statutory role is to plan, manage and monitor the design work, and to coordinate design so that, so far as reasonably practicable, if the building is built in accordance with that design, it will comply with all relevant requirements of the Building Regulations, including Schedule 1 and Regulation 7 on materials and workmanship.

Now, individual Designers, including specialist consultants like structural and fire engineers, and design‑and‑build subcontractors, remain responsible for the compliance of their own design work.

The Principal Contractor, similarly to the Principal Designer, must plan, manage and monitor but relating to the building work so that the construction complies with the Building Regulations, and they must coordinate contractors on site to that end. 

It’s important to note that the Principal Designer does not “take over” compliance from other designers but instead, they coordinate and manage the process so that everyone’s design work collectively leads to a compliant building. That distinction is crucial when we get to specialist design under a Principal Contractor.

Now, what happens when the Principal Contractor takes on design control and specialist design, where does responsibility lie:

This is a particularly common route under design and build procurement, where the contractor appoints subcontractors for cladding, façade, MEP services, fire systems, and so on, and each possesses design responsibility respectively into their packages.

Now, here’s the core issue:

• Specialist subcontractors are Designers under the regulations in their own right. They each have a duty to ensure their design complies with the relevant Building Regulations requirements.
• The Principal Designer has to coordinate those design activities to ensure that, taken together, the design would deliver a compliant building if constructed as designed.
• The Principal Contractor is then responsible for planning, managing and monitoring the building work, and ensuring that what is built complies.

On many design and build projects, once the design team is novated, the contractor is effectively the designer in control of design work for the purposes of the dutyholder regime. So that’s the pivot point, if the Principal Contractor is now the party controlling and directing specialist design, they may need to be appointed as Principal Designer as well as Principal Contractor, provided they are competent to do so. The professional risk question here though is, if the Principal Contractor is in that position, who has design responsibility for specialist design compliance and how far does that extend up the chain to you as architect?

So under a typical Design and Build Scenario when the Principal Contractor becomes the “designer in control” the process leading up to that tends to be that:

First, the initial design team is often initally appointed by the client and may act as lead designer and sometimes as Principal Designer in the early stages.

Then at contract award, that design team is novated to the contractor, who then becomes responsible for taking the design through to completion, including managing specialist design packages.

Its at this point, when the design team is novated, that the main contractor should usually be appointed both as Principal Designer and Principal Contractor by the client, because the contractor has become the designer in control of the design work.

The key legal detail is that the Principal Designer role cannot itself be novated, the appointment must come directly from the client, because the Building Regulations require the client to make that appointment. So the contractor can’t simply assume that because the design team has been novated under the building contract. They have now picked up the statutory Principal Designer role and therefore a fresh appointment is needed.

Now, when the contractor is controlling specialist design by issuing design briefs, approving subcontractor designs, instructing changes, and so on, they are, in effect, the designer in charge. In that situation, the contractor should be made Principal Designer, subject to demonstrating competence, and cannot offload that statutory liability onto their consultants or subcontractors.That has two consequences for specialist design:

• The Principal Contractor‑as‑Principal‑Designer must ensure that all specialist design is coordinated and managed so that the design as a whole could lead to compliance.
• And that specialist designers still retain direct responsibility for the compliance of their own detailed designs.

So who is utlimately responsible for specialist design compliance:

Let’s break this down, starting with Individual specialist designers:

Each specialist subcontractor or consultant that carries out design work is a Designer under the Building Regulations dutyholder regime. That means: 

• They must ensure that their own design work complies with the relevant requirements of the Building Regulations.
• They must cooperate with the Principal Designer and Principal Contractor, share relevant information and take account of coordinated design decisions.

So the façade subcontractor is responsible for the compliance of the façade design, the MEP contractor for the services design, and so on. Their liability is direct and cannot be “absorbed” by the Principal Contractor or Principal Designer.

Now, relating to the Principal Designer’s coordinating duty:

Under the Building Regulations, the Principal Designer has an explicit duty to plan, manage and monitor design work and to coordinate matters relating to design so that all reasonable steps are taken to ensure that, if the building is built in accordance with that design, the building work would comply with all relevant requirements. Crucially:

• The Principal Designer is not responsible for “signing off” that every element of design is compliant. That evidential responsibility remains with the individual Designers.
• Their duty is instead to make sure the process of design, coordination and information exchange is robust, and that conflicts and gaps are resolved so that compliance is achievable.

While Designers remain responsible for compliance of their own designs, the Principal Designer has to ensure good communication, coordination and collaboration between them so the project as a whole will be compliant.

Now, as mentioned, the Principal Contractor’s responsibility for building work is for planning, managing and monitoring the building work, ensuring that what is constructed complies with Building Regulations. They must:

• Coordinate contractors and construction activities on site.
• Must ensure an adequate frequency of inspections of the work for “safety occurrences” on higher‑risk building projects, under the Higher‑Risk Buildings Procedures regulations.
• They cannot simply delegate away their statutory responsibilities, though they may subcontract work, they retain the overarching legal duty as Principal Contractor.

So if the Principal Contractor has become the designer in control of design work, they should also be appointed as Principal Designer. In that combined role, the contractor is responsible for:

• Coordinating specialist design work.
• Ensuring that, through design management and coordination, the design on which the work is based can achieve compliance.
• Ensuring the construction of that design complies in practice.

So to clarify the positions, under a Principal Contractor who is controlling specialist design:

• Specialist designers are responsible for their own design compliance.
• The Principal Designer, often in this scenario the Principal Contractor, is responsible for coordinating design work and for taking all reasonable steps to ensure the design, as a package, could lead to compliance.
• The Principal Contractor is responsible for compliance of the building work on site, including work carried out under specialist design.

The key thing to make clear here is that statutory liability for the Principal Designer role cannot be transferred to a consultant or subcontractor by the Principal Contractor. The appointment flows from the client, and the legal responsibility sticks to whoever has that appointment.

Now, what is the situation on Higher‑risk buildings and inspection processes:

On higher‑risk buildings, the picture tightens further. The Building (Higher‑Risk Buildings Procedures) (England) Regulations 2023 introduce additional duties.

• The Principal Designer must ensure an appropriate frequency of inspections of Higher-Risk Building design work for safety occurrences throughout the construction phase. This is about inspecting the design work, not the physical construction.
• The Principal Contractor has a parallel duty to ensure an adequate frequency of inspections of the construction work itself for safety occurrences.

Persons carrying out the Principal Designer role are cautioned against traditional site inspection duties that architects might carry under their separate professional appointments. A Principal Designer completion statement confirms that they have complied with their Part 2A duties, not that the building is compliant in all respects.

For specialist design, this means:

• The Principal Designer must ensure that specialist design work feeding into a higher‑risk building is subject to appropriate checking and review at design level.
• The Principal Contractor must ensure that the built work corresponding to that specialist design is inspected at appropriate intervals for safety occurrences.

Again, individual specialist designers remain directly responsible for their own design compliance, even in the higher‑risk regime.

So if considering taking on the Principal Designer role, consultants are urged to:

Only accept the role where the individual or organisation has the skills, knowledge, experience and behaviours necessary for the specific project. That applies whether you’re being asked to act as Principal Designer directly for the client, or to advise a Principal Contractor who has been appointed as Principal Designer.

Key points for practices:

• The lead designer is often well placed to be Principal Designer, but only if competent for the project type and scale.
• Architects should refuse appointments, including Principal Designer, if the role exceeds their competence.
• Where the Principal Contractor is appointed as Principal Designer, the former lead architect may take an advisory role, if PI cover allows, without assuming the statutory Principal Designer duty.

To conclude:

• Under the Building Regulations dutyholder regime, specialist designers remain directly responsible for the compliance of their own design work as Designers.
• The Principal Designer is responsible for planning, managing and monitoring the design work, coordinating all designers so that, as far as reasonably practicable, the design as a whole could result in a compliant building if constructed. They do not “take over” compliance from others.
• The Principal Contractor is responsible for planning, managing and monitoring the building work on site, ensuring that what is built complies with Building Regulations.
• On design and build projects where the contractor becomes the designer in control of design work, especially where they control specialist design packages, they should be appointed as both Principal Contractor and Principal Designer by the client, subject to competence.
• The Principal Contractor cannot novate or delegate away the statutory Principal Designer role to a consultant or subcontractor; that appointment and its liability remain with whoever the client appoints as Principal Designer.
• For higher‑risk buildings, the Principal Designer must ensure appropriate inspections of design work for safety occurrences, while the Principal Contractor must ensure adequate inspections of construction work.