Building Regulations and scope of work for bricklayers: who is responsible for what

TL;DR: Building Regulations in England and Wales are administered by Building Control: either the local authority or an approved inspector. Sign-off authority rests with the principal contractor or the designer for the project, not with the bricklayer delivering the physical work. A bricklayer's responsibility is workmanship: building accurately and carefully to the specification they have been given. The specification itself, whether it complies with Building Regulations, is the designer's and the principal contractor's responsibility. A scope of works document that is clear about this boundary protects the bricklayer from inadvertently absorbing risk that belongs to someone else. CDM 2015 Principal Contractor duties apply only on notifiable projects above defined thresholds; most sole-trader bricklayers work as subcontractors and are not the Principal Contractor. This post explains how Building Regulations responsibility is allocated across a typical project, how CDM 2015 thresholds work in practice, and how to write a scope of works that does not accidentally absorb someone else's liability.

Building Regulations exist to set minimum standards for design and construction work in England and Wales. They cover structural integrity, fire safety, thermal performance, accessibility, drainage, and ventilation, among other things. They are enforced through Building Control, a statutory function carried out by the local authority building control service, or by an approved inspector (a private sector body authorised to carry out Building Control functions).

Understanding where Building Regulations responsibility sits is not a technicality. It is directly relevant to how a bricklayer writes their scope of works, how they phrase their quotes, and how they protect themselves if a dispute arises about whether a project passed Building Control inspection.

The most useful way to think about responsibility on a building project is in three categories: what the designer is responsible for, what the principal contractor is responsible for, and what the bricklayer (as a subcontractor) is responsible for. These categories do not always sit in the same person or organisation. On smaller projects they sometimes overlap, but understanding them separately makes the scope of works question much clearer.

The designer (typically an architect, structural engineer, or architectural designer) is responsible for producing a specification that complies with Building Regulations. When a structural engineer produces a drawing specifying a particular wall construction, the mortar mix, the wall tie frequency, the lintel schedule, and the concrete specification for a foundation, they are producing a design that, if built to specification, should comply with the relevant parts of Building Regulations.

The designer's warranty is not that the building will automatically pass Building Control. It is that their design, competently executed, meets the regulatory requirements. If the design is wrong, for example if the structural engineer specified an inadequate lintel and it fails, that is a design failure, not a construction failure.

This distinction matters for a bricklayer because: if you build correctly to the structural engineer's drawing and the project fails a Building Control inspection because the drawing was wrong, that failure is not your liability. You built to specification. Documenting what specification you built to, and that you built to it, is the evidence that protects you.

The principal contractor is the party with overall responsibility for how the project is delivered. On most domestic building jobs where a main contractor is running the project and the bricklayer is a subcontractor, the main contractor holds the principal contractor role.

The principal contractor is responsible for:

• Ensuring that Building Control notifications are made at the right stages (usually commencement and completion).
• Managing the Construction Phase Plan under CDM 2015 on notifiable projects.
• Coordinating the different trades and ensuring that the work of each subcontractor fits together to produce a compliant result.
• Making the Building Control inspection application at completion and managing any matters the inspector raises.

The critical point for bricklayers: if you are a subcontractor engaged by a principal contractor, Building Control sign-off is the principal contractor's responsibility, not yours. You are responsible for delivering your specific scope of work to the specification you were given. You are not responsible for whether the overall project achieves Building Control approval.

If the project does not achieve Building Control approval and the reason is a problem with your brickwork (incorrect coursework, missing cavity insulation that you were specified to install, wall tie spacing outside the specification), then you bear responsibility for your scope of works. If the reason is something in the design, the drainage, the structural engineer's specification, or the principal contractor's overall coordination, that does not cascade to you.

A bricklayer's responsibility is workmanship. You warrant that:

• The brickwork is laid to the specified dimensions, heights, and level.
• The mortar mix used is as specified.
• The bond pattern is as specified.
• Wall ties are installed at the specified frequency and in the specified position.
• Cavity closers, lintels, and DPC are installed as specified.
• The finished work is plumb, level, and fair-faced to the specification.
• Any departure from the specification that arises during the work (an obstruction encountered, a discrepancy in the drawings, a site condition not accounted for in the design) is communicated to the client or principal contractor promptly.

You do not warrant that the specification you were given is structurally correct. You do not warrant that the project will pass Building Control. You do not warrant that the designer's drawings comply with Approved Document A (structure) or any other Approved Document. Your warranty is workmanship to spec.

This is not a way of avoiding responsibility. It is an accurate description of what a trade contractor warrants. A bricklayer who builds incorrectly (who drifts off plumb, skips wall ties, uses the wrong mortar mix) is in breach of their contract and responsible for rectification. A bricklayer who builds correctly to a specification that turns out to be wrong is not.

The Construction (Design and Management) Regulations 2015 (CDM 2015) create specific duties for designers, principal designers, contractors, and principal contractors on construction projects. Understanding where most bricklayers sit within this framework is important, because CDM 2015 is sometimes treated as a broader burden than it actually is for sole-trader bricklayers.

CDM 2015 applies to all construction work. Every contractor has basic duties: to plan, manage, monitor, and coordinate work under their control so that it is carried out without risks to health and safety; to cooperate with the principal contractor; to provide relevant information to the principal designer; and to comply with any reasonable directions from the principal contractor.

These duties apply regardless of project scale. They are not onerous for a bricklayer working as a subcontractor: plan your work safely, use appropriate PPE, follow the site rules, communicate hazards.

A project becomes notifiable under CDM 2015, triggering the more formal Principal Contractor and Principal Designer appointment requirements, when it is likely to involve:

• More than 30 working days with more than 20 workers simultaneously on site; or
• More than 500 person-days of construction work in total.

Most domestic bricklaying projects (a garden wall, a house extension, an outbuilding, even a full rear addition to a domestic property) will not reach the 500 person-day threshold unless they are large and complex. A bricklayer laying an extension for three weeks is not on a notifiable project in most cases.

For notifiable projects: the client (or someone appointed by the client) must appoint a Principal Designer and a Principal Contractor. The Principal Contractor takes on additional CDM duties including producing and maintaining the Construction Phase Plan, managing site welfare provisions, and coordinating health and safety across the project.

Most bricklayers work as subcontractors on projects where someone else (a main contractor, a building firm, a developer) is the Principal Contractor. In that case, CDM 2015 Principal Contractor duties do not fall on the bricklayer.

There are situations where a bricklayer effectively runs the whole project, contracted directly by the domestic client, engaging their own subcontractors, and managing the site. If that project reaches the notifiable threshold, the bricklayer is the Principal Contractor and the additional CDM duties apply to them.

We'd say so plainly: most sole-trader bricklayers on domestic work are not running notifiable projects and are not Principal Contractors. But the question is worth asking explicitly for any project involving multiple trades over an extended programme.

The CDM position has direct implications for what your scope of works should say. A scope of works that accidentally includes language suggesting you are taking on Principal Contractor responsibilities (such as "we will manage all Building Control submissions" or "we are responsible for health and safety on site" without qualification) can create a liability you did not intend to take on.

A scope of works for a bricklayer who is a subcontractor on someone else's project should state:

• You are engaged as a bricklaying subcontractor.
• You will comply with all site health and safety rules as directed by the principal contractor.
• Building Control submissions and inspections are the responsibility of the principal contractor (or the client, if directly engaged on a domestic project outside the CDM notifiable threshold).
• Your scope is limited to [specific brickwork described].

A scope of works for a bricklayer who is running the project directly for a domestic client should be clear about whether CDM Principal Contractor duties apply and, if they do, whether the bricklayer is taking them on or whether the client needs to appoint someone to that role.

Most disputes can be traced to a scope of works that was either too vague or that accidentally included language absorbing responsibilities that were not intended. Non-payment disputes and legal proceedings rarely arise from genuinely ambiguous situations. They arise from documents that did not say clearly enough who was responsible for what.

Three categories of risk that bricklayers most commonly absorb by accident:

Design risk. A scope of works that says "build the extension to the agreed design and all applicable Building Regulations" absorbs design risk if the agreed design turns out not to comply. The correct framing: "build the extension to the structural engineer's drawing reference [X], dated [Y], and to the specification sheet reference [Z]." You are building to a specification. If the specification is later found to be non-compliant, the trail points to the specification, not to your workmanship.

Coordination risk. A scope that says "complete all brickwork including interfaces with drainage, windows, and roofing" absorbs coordination risk if the window installer has not been to site yet and the aperture position turns out to be wrong. The correct framing: "complete brickwork for window apertures in accordance with the window supplier's schedule, coordinated by the principal contractor." Your work depends on coordination information you have been given. Responsibility for the accuracy of that information sits with whoever produced it.

Approval risk. Any language that implies you are responsible for Building Control approval absorbs approval risk. Never include language like "guaranteed to achieve Building Control sign-off" or "all work carried out to satisfy Building Regulations." The correct framing: "all brickwork carried out to the specification provided, to professional trade standards, in accordance with current building practice." That is what you can warrant. Building Control sign-off is a separate statutory process that you are contributing to by doing good work. It is not a warranty you can give unilaterally.

A bricklayer's scope of works should follow a structure that makes the boundaries of responsibility explicit from the first line. A useful template structure:

1. Job description. One paragraph describing the project, the parties, and the site. "Supply and lay brickwork for the rear extension to [address] on behalf of [client name], to the drawings provided by [designer] referenced [drawing numbers and dates]."

2. Included works. Bullet list of what is included: setting out, brickwork to specified courses, mortar mix, wall ties, lintels, cavity closers, DPC, pointing, cleaning off. Be specific. If you are not laying the foundations, say so.

3. Excluded works. Bullet list of what is explicitly excluded: foundations (by others), scaffolding (by others), window installation (by others), drainage connections (by others), Building Control submissions (by principal contractor/client), structural engineering sign-off (by designer). Specific exclusions are your protection against scope creep at the point of dispute.

4. Materials. Who supplies, to what specification, and what happens to over-ordering and waste.

5. Access and site conditions. What access the client/principal contractor will provide, and what happens if site conditions depart materially from what was described.

6. Variation procedure. Written agreement required before any work outside this scope is carried out.

7. Workmanship warranty. You warrant that all brickwork is carried out to professional trade standards, plumb, level, and to the specification provided. This is your warranty: workmanship, not design compliance.

8. Insurance. Your public liability insurance limit and (if applicable) employers' liability if labour is engaged.

This structure does two things. It protects you from absorbing risk that belongs elsewhere, and it sets a clear baseline for any dispute about what was and was not in scope.

If you do nothing else before your next job: add an explicit excluded works section to your scope of works. List the things that are not your responsibility by name. Design sign-off, Building Control submissions, structural engineering, drainage, scaffolding. Four lines of text that prevent months of argument.

Your public liability insurance covers third-party claims arising from your work. It does not cover claims arising from design failures that were not your specification. Maintaining a clear document trail (drawings referenced in your scope, photos of work at each stage, a signed completion document) means that if a claim is made, the trail runs from the claim back through your scope to the correct party.

Employers' liability insurance is a legal requirement if you engage workers, including labour-only subcontractors who are not themselves self-employed. Check your cover applies to the labour arrangements you use. CIS subcontractors who are genuinely self-employed and supply their own tools typically fall outside the employers' liability requirement, but this depends on the specific working arrangement.

For the full document set, including client contract, scope of works template, RAMS, waste log, and sign-off sheet, see essential business documents for UK bricklayers.

For the marketing copy side, including how to write about your work accurately without over-claiming on Building Regs or engineering quality, see AI copy kit for bricklayers.

LaunchKit's bricklayer business documents bundle includes a scope of works template built with the liability boundaries described in this post, plus a client services contract, RAMS template, and sign-off document. All structured for bricklaying work specifically. £19.99.

The bundle pairs with the bricklayer MTD Compliance Kit (£16.99) for quarterly tax record-keeping. If your marketing copy also needs attention, the bricklayer AI Copy Kit (£14.99) covers the copy side with prompts already structured to avoid Building Regs overclaims.

This article is general guidance, not legal advice. CDM 2015 and Building Regulations are substantive regulatory frameworks. For your specific position on a project, including whether you are the Principal Contractor, whether the CDM notifiable threshold applies, or how Building Control responsibilities are allocated in your contract, consult a solicitor or a CDM coordinator with construction sector experience.