Understanding building regulations
Building regulations set minimum standards. Most work requires approval. An architect prepares drawings while a principal designer manages health and safety compliance.
When approval is needed
Required for most building work including extensions, structural alterations, changes of use, replacement windows, electrical and plumbing work, and heating systems.
The application process
Two routes: full plans application (drawings checked before work starts) and building notice (notify and inspect during construction). Full plans is recommended for anything beyond the simplest work.
Common requirements
The regulations cover structural stability, fire safety, moisture resistance, thermal performance, ventilation, electrical safety, drainage, accessibility and sound insulation.
Inspections and completion
Building control inspects at key stages. A completion certificate is issued when satisfactory. This certificate is important for future property transactions.
Building Regulations approval is separate from planning
A recurring and costly misunderstanding is treating planning permission and Building Regulations approval as the same consent. They are independent. Planning controls what may be built and how it looks in its context; Building Regulations control how it is constructed - structure, fire safety, thermal performance, ventilation, drainage, accessibility. A scheme can have planning permission and still be unlawful to occupy without Building Regulations sign-off, and vice versa.
For most London works both consents are needed and should be programmed together. The Building Safety Act has also changed the regime for higher-risk buildings, where the new gateway regime and the Building Safety Regulator's role add steps that must be planned for early rather than discovered late.
Full plans vs building notice, and completion certificates
For domestic and smaller works there are two routes: a full plans application, where the design is checked and approved before work starts (lower risk, recommended for anything structurally significant), and a building notice, which is faster to start but offers no pre-construction design check and carries more risk if non-compliant work has to be opened up later.
The document that matters at the end is the completion certificate. Its absence routinely delays or derails property sales when a buyer's solicitor finds works carried out without evidence of compliance. We advise on the right route, what building control will expect, and how to regularise historic work that was completed without a certificate.
Frequently asked questions
Planning permission vs building regulations?
Planning controls what and where. Building regulations control how. Both may be needed.
Can I start before approval?
With building notice you can start after giving notice. With full plans, wait to avoid non-compliant work.
What if I do work without approval?
The local authority can take enforcement action. Lack of approval causes problems when selling.
Do internal alterations need approval?
Structural alterations, electrical work and fire safety changes usually do. Cosmetic changes do not.
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Savas Bulduk
BSc (Hons) MRICS, Director & Chartered Building Surveyor.
Writes on Building surveying, Fire safety and facade, External wall systems, Technical due diligence, Contract administration. See the full team profile.