Competence is a legal duty on every building job in England

On 1 October 2023 competence stopped being a professional aspiration in England and became a legal requirement on every building job. Not on high-rise blocks. Not on work over a value threshold. On any building work at all, including a bathroom in a terraced house.

The instrument is the Building Regulations etc. (Amendment) (England) Regulations 2023, SI 2023/911, which came into force on 1 October 2023 and inserted a new Part 2A — Dutyholders and competence into the Building Regulations 2010.

Most of the coverage at the time was about tall buildings, and the higher-risk regime genuinely is a separate and stricter thing. That coverage left a wrong impression behind, and it is the reason a lot of small firms have never read the duties that apply to them.

The requirement itself

Regulation 11F(1):

Any person carrying out any building work or any design work must have — (a) where the person is an individual, the skills, knowledge, experience and behaviours necessary, (b) where the person is not an individual, the organisational capability, to carry out — (i) the building work in accordance with all relevant requirements …

Three things in that one sentence deserve reading twice.

"Any person carrying out any building work." No threshold. No exclusion for domestic work, for small jobs, or for work that is not notifiable.

Skills, knowledge, experience and behaviours. Four things, and the fourth is not a qualification. Behaviours cover how you work — whether you raise a problem you have spotted, whether you decline work you cannot do.

Organisational capability for anyone who is not an individual. A limited company cannot hold skills; it holds capability. Under regulation 11F(2) the same requirement extends to fulfilling the duties of a contractor or designer under the regulations, which is a second and separate thing from being able to do the work.

Regulation 11F(3) and (4) deal with trainees: the requirements do not apply to an individual in training to fulfil them, and the person who asked them to do the work "must ensure T is adequately supervised when carrying out the work". Regulation 11F(5) closes the obvious gap — someone in training for the role may not be appointed as a principal contractor or principal designer.

Regulation 11I adds a duty nobody expects: if you cease to satisfy the competence requirement in relation to work you are doing, you must say so. A contractor tells the person who engaged them and the principal contractor; a principal contractor tells the client.

The duty to check the other person

Competence is only half of Part 2A. The other half is regulation 11E, and it is the one that changes how a small firm engages labour.

Where a person (P) proposes to use another person (A) to carry out building or design work, then before permitting A to carry out any work:

P must take all reasonable steps to satisfy themself that A — (i) fulfils the requirements in regulation 11F(1) and (2) … or (ii) is an individual who is in training … and arrangements have been put in place to supervise A

and, under 11E(3), P must additionally take all reasonable steps to satisfy themselves that A is able to fulfil the general duty in regulation 11J to plan, manage and monitor.

"All reasonable steps to satisfy themself" is the standard, and it is not satisfied by a card being waved at you. What it is satisfied by depends on the work, but the shape of an answer is: what did you ask, what did you see, and what did you write down.

For two trades the answer is already written into other regulations. Engaging someone on the Gas Safe Register is the competence the law separately requires for gas work, covered in what regulation 3 actually requires of you. Electrical work has its own version in the Part P self-certification schemes, set out in which electrical jobs are notifiable, and how to sign off.

For higher-risk building work, 11E(2)(b) adds a specific question you must put: whether "a serious sanction has occurred, in relation to them, within the 5 years ending on the date of the appointment", and you must consider any information available to you about their misconduct. Regulation 11E(8) defines a serious sanction as a compliance notice referring to Part A (structure) or Part B (fire safety), a stop notice, a conviction under the Building Act 1984, the Health and Safety at Work etc. Act 1974, the Building Safety Act 2022 or the Regulatory Reform (Fire Safety) Order 2005, or an adverse finding in a published inquiry report.

Who is who

Regulation 3 of SI 2023/911 inserted the definitions, and they are broader than the words suggest.

Two consequences that catch trades out.

"Manages or controls" makes you a contractor without lifting a tool. A firm that takes a job and subcontracts all of it is a contractor under this definition.

Designing is not restricted to architects. A heating engineer who sizes a system, or a builder who decides how an opening will be supported, is carrying out design work and is a designer for that work.

Domestic clients: the duties move to you

Regulation 11C is the provision every firm working for householders needs to know, because it transfers the client's duties onto the trade.

Where the client is a domestic client, the duties in regulations 11A(1) to (3) — making and maintaining suitable arrangements for planning, managing and monitoring the project so as to ensure compliance — and in 11E(2) to (5) must be carried out by:

• where there is only one contractor, the contractor;
• where there is more than one, the principal contractor, or the principal designer if the client and the principal designer agree in writing.

And regulation 11C(2) closes the gap where a householder makes no appointments at all: the designer in control of the design phase is the principal designer, and the contractor in control of the construction phase is the principal contractor. There is no state in which nobody holds the role.

So on a domestic extension the householder does not plan, manage and monitor the project for regulatory compliance. You do, whether or not anyone told you so, and whether or not it was priced.

Principal designer and principal contractor

Regulation 11D(1): where there is more than one contractor, or it is reasonably foreseeable that there will be, the client must appoint in writing a designer with control over the design work as principal designer, and a contractor with control over the building work as principal contractor.

Timing. Before the construction phase begins; or, where the project includes higher-risk building work needing an application to the regulator, before that application is submitted (regulation 11D(3)).

The CDM shortcut. Regulation 11D(2) lets a client certify in writing that the CDM principal designer or CDM principal contractor is treated as appointed for these regulations too. That is a sensible saving, and it is not automatic — someone has to write the certificate.

Sole contractor. Regulation 11D(6): where there is only one contractor on a project, that contractor "is to be treated as appointed as the principal contractor and must fulfil the duties of the principal contractor set out in these Regulations". Where 11D(6) applies and there is only one designer, that designer must fulfil the principal designer duties; where there is more than one, they must agree in writing which of them is the lead designer and give the client a copy of the agreement.

No appointment made. Regulation 11D(5): where the client fails to appoint, the client must fulfil those duties themselves until they do. That does not apply to domestic clients, because regulation 11C(3) disapplies it — which is exactly how the duties end up back with the contractor.

What the duties actually require

Regulation 11J is the general duty and it is short: building work must be "planned, managed and monitored so as to be in compliance with all relevant requirements", and everyone carrying out building work must cooperate with the client, the designers and the other contractors to the extent necessary to achieve that.

Regulation 11L adds the contractor's specific duties:

1. Do not start any building work unless satisfied that the client is aware of the duties the client owes under all relevant requirements.
2. Ensure the work complies, and give every worker under your control "appropriate supervision, instructions and information" so that it does.
3. Take all reasonable steps to provide sufficient information about the work to help the client, other contractors and designers comply.
4. Where you are doing part of the work, consider the other work that directly relates to yours and report any concerns about compliance to the principal contractor.
5. Advise on whether work is higher-risk building work if asked.

Duty 1 is the surprising one. Before you start, you must be satisfied the client knows their own obligations. On a domestic job, telling the householder in writing what building control approval is needed and who is arranging it is not customer service — it is duty 1 discharged and evidenced.

Duty 4 is the surprising one for subcontractors. A plumber who sees that the joiner has notched a joist in a way that will not comply does not get to say it was not their trade. The duty is to consider directly related work and report concerns to the principal contractor.

Regulation 11M(5)(b) adds a deadline worth knowing if you take principal designer roles: when the appointment ends, "no later than 28 days after the end of the appointment", give the client a document explaining the arrangements put in place to fulfil the duties.

Enforcement, and the ten years

Three provisions of the Building Act 1984, all reshaped by the Building Safety Act 2022.

Section 35 — the offence. "A person who contravenes a provision of building regulations, or a requirement imposed by virtue of any such provision, commits an offence." On conviction on indictment: imprisonment for up to two years or a fine, or both, with a further daily fine at level 1 for each day the default continues after conviction. The section was substituted by the Building Safety Act 2022 with effect from 6 April 2023.

Section 35B — compliance notices. The building control authority may require a person to take specified steps, or to remedy the contravention, within a specified period. Contravening the notice without reasonable excuse is itself an offence with the same penalties. Section 35B(6) limits when the notice may be given: not "in respect of a contravention which occurred more than 12 months before the day on which the notice is given".

Section 36 — enforcement notice, and the number that changed everything. Section 36(4) now provides that a notice may not be given more than 10 years from the date of the completion of the work in question. It used to be twelve months.

Ten years is longer than most firms keep their job records, longer than many trading names last, and considerably longer than anyone's memory of who did what on a given job. That is the practical consequence of Part 2A for a small business, and it has almost nothing to do with competence in the abstract: you may be asked, nine years from now, to show what you did and what you checked.

What this means on Monday

1. Write down what you checked before engaging anyone. Regulation 11E is a "reasonable steps" duty, and reasonable steps you cannot evidence are the same as none.
2. On domestic jobs, assume the client's planning and monitoring duties are yours. Regulation 11C puts them there, and the householder will not know it.
3. If you are the only contractor, you are the principal contractor. Regulation 11D(6) is automatic.
4. Tell the client in writing what they are responsible for, before you start. That is regulation 11L(1), and it is one paragraph in your acceptance letter.
5. Report compliance concerns about adjacent work in writing. Regulation 11L(4) makes it a duty, and a verbal mention on site is worth nothing when the question is asked years later.
6. Keep job records for at least ten years. Section 36(4) is the reason, and it applies to work already completed since the amendment came into force.

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Position as at 29 August 2026. This article describes the law and is not legal advice. The Building Regulations 2010 as amended by SI 2023/911 apply in England; Wales, Scotland and Northern Ireland run separate building standards systems. Higher-risk building work carries substantial additional duties, including the gateway procedures, which are outside the scope of this article.

What Zirko does here: the job holds who was engaged, what was agreed, what was sent to the client and when — which is the material a "reasonable steps" question is answered from, and it stays readable for as long as you keep it. Zirko does not assess anyone's competence, does not make appointments and is not a substitute for the checks regulation 11E requires.