Building regulations explained for homeowners
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Short answer: building regulations are the legal minimum standards for how building work is carried out, covering structure, fire safety, insulation, ventilation, electrics and more. They apply to almost all extension and renovation work whether or not planning permission is needed, and they are checked by building control through inspections during the build. At the end you get a completion certificate, and gov.uk notes you usually receive it within 8 weeks of completing compliant work. Solicitors ask for that certificate when you sell, so it matters.
Planning permission and building regulations are different things
Planning is about whether the building should exist: its size, look and effect on neighbours. Building regulations are about whether it is built properly. An extension can be permitted development and still need building regulations approval; almost all do.
The two application routes
- Full plans. Drawings and structural details are submitted and checked before work starts, then inspected on site at key stages. Slower to start, fewest surprises. This is the route we use for structural projects.
- Building notice. Work starts on 48 hours' notice without prior plan checking, and compliance is assessed entirely on site. Faster to start, but problems are found in built work, at your cost. gov.uk notes you do not get formal approval as you do with full plans.
Not sure which route fits your project? A free consultation talks it through, with no obligation.
Book a Free ConsultationWho checks the work
Building control, either the council's team or a registered building control approver, inspects at set stages: foundations, structure, insulation, drainage and completion. Separately, some trades self-certify through competent person schemes; our electricians are NICEIC approved, so electrical work is certified without a separate building control application for that element (gov.uk: building regulations approval).
Keep every certificate. Completion certificate, electrical certificates, glazing and appliance registrations: they all go in your handover pack. Missing paperwork surfaces years later, in a sale, as your problem.
When this is not what you want to hear
If a quote is dramatically cheaper because the job will run on a building notice with no drawings, no structural calculations and no named building control body, that discount is your risk being repriced as your problem. Regularising unapproved work after the fact costs more than doing it properly the first time.
Quick answers
Does my extension need building regulations approval if it is permitted development?
Almost certainly yes. Permitted development answers the planning question only. Building regulations apply to the work itself, and building control inspects during the build.
What is a completion certificate and when do I get it?
The document confirming building control is satisfied the work complies. Per gov.uk, you usually receive it within 8 weeks of completing compliant work. Keep it; buyers' solicitors ask for it.
Do electricians need a separate building control application?
Not when the work is done by someone registered with a competent person scheme, which lets registered tradespeople certify their own work. Our electricians are NICEIC approved.
Next step: a free consultation on your actual project, or browse the rest of the advice hub.