Who does what under the Building Safety Act: the dutyholders

Why did the Act create dutyholders?

Because the Hackitt review found a system where responsibility was so diffuse that, in practice, nobody held it. The answer, in force since 1 October 2023 through Part 2A of the Building Regulations, borrows the structure construction already understood from CDM: named roles, defined duties, and personal consequences. The difference is the subject matter. CDM dutyholders manage health and safety; BSA dutyholders own compliance with building regulations itself.

The cast during design and construction: the client, the principal designer, the principal contractor, and beneath the principals every designer and contractor on the job. On higher-risk buildings the same roles carry additional procedural duties through the gateway regime, and the regulator expects to see each appointment made, in writing, before work it governs begins.

What does each dutyholder actually own?

Dutyholder	Owns	The line that bites
Client	Making suitable arrangements, appointing competent principals	The project's compliance culture is set here, and the client signs a statement at Gateway 2
Principal designer	Planning, managing and monitoring design compliance	The design, if built, must comply; "contractor to resolve" is no longer a design strategy
Principal contractor	Planning, managing and monitoring construction compliance	Building what was approved, controlling change, and evidencing both
Designers and contractors	Their own work complying	Competence is personal, not inherited from the appointment

The client's position deserves emphasis because it is the least understood. The Act treats the client as the source of the project's arrangements: who gets appointed, whether they are competent, whether time and money exist to do compliance properly. On a higher-risk building the client also signs a statement in the Gateway 2 application itself, which concentrates the mind.

What does competence mean here?

Something specific: the skills, knowledge, experience and behaviours, or for organisations the capability, to carry out the work in question. The PAS 8671, 8672 and 8673 specifications flesh this out for principal designers, principal contractors and building safety managers respectively, and dutyholders on higher-risk buildings make competence declarations as part of the gateway process.

The regulator's expectation is that competence is demonstrated, not asserted. An appointment letter that names a principal designer without evidence the organisation can discharge the Part 2A duty is exactly the kind of gap the BSR's validation process has learned to find, and one of the recurring reasons applications fail.

What happens at handover, and who takes over?

At Gateway 3 the principal designer and principal contractor sign compliance declarations, the as-built golden thread passes to the building's owner, and the regime changes cast: the accountable person, and where there are several, the principal accountable person, take over for the occupation phase. The PAP registers the building, manages the safety case, and lives with the information the construction team handed across.

That handover is where the construction-phase roles are tested in hindsight. Declarations signed at completion rest on records built across the whole job: what was designed, what changed under change control, and what was actually installed. Dutyholders who kept contemporaneous evidence sign with confidence; dutyholders reconstructing the story from memory and a photo-less email chain discover what their signature really costs.