Summary

The Building Regulations are the rulebook that says a finished building must be safe, healthy, accessible and reasonably energy-efficient — and unlike a lot of "guidance" in construction, they are law. They are made under the Building Act 1984 and they apply to most building work: new builds, extensions, structural alterations, changes of use, and a long list of specific jobs like replacing a boiler, rewiring, fitting windows, or building a new chimney. Failure to comply is an offence, and a local authority can require non-compliant work to be put right or removed.

The structure is worth learning because it is how the whole industry refers to the rules. The technical requirements are grouped into Parts, lettered A onwards — Part A is structure, Part B is fire safety, Part L is the conservation of fuel and power, Part P is electrical safety, and so on. Each Part is short and sets out what must be achieved. Alongside each sits an Approved Document (the "AD"), which gives detailed, practical guidance on how to achieve it. The Approved Documents are not the only way to comply — you can demonstrate compliance another way — but following the relevant AD is the standard, accepted route, and "I built it to the Approved Document" is the answer Building Control expects.

The two ideas tradespeople most often get muddled are: first, Building Regulations are not planning permission — they are entirely separate systems with different purposes, and you can easily need one without the other; and second, the difference between Building Control approval and a Competent Person Scheme. For notifiable work you either tell Building Control (a Building Notice or Full Plans application, with inspections and a completion certificate), or — for certain trades — you self-certify through a registered scheme like Gas Safe, NICEIC/NAPIT (electrical) or FENSA (windows). Getting that route right is what produces the certificate the customer needs when they sell.

Key Facts

Quick Reference Table

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The Parts of the Building Regulations (England) and what each covers:

Part Topic
A Structure
B Fire safety
C Site preparation and resistance to contaminants and moisture
D Toxic substances
E Resistance to the passage of sound
F Ventilation
G Sanitation, hot water safety and water efficiency
H Drainage and waste disposal
J Combustion appliances and fuel storage systems
K Protection from falling, collision and impact
L Conservation of fuel and power
M Access to and use of buildings
N (Glazing — now largely absorbed into Part K)
O Overheating
P Electrical safety (dwellings)
Q Security (dwellings)
R Physical infrastructure for high-speed electronic communications
S Infrastructure for charging electric vehicles

Detailed Guidance

Building Regulations vs planning permission — keep them separate

This is the single most common source of confusion, so be clear with customers:

They are independent. A loft conversion may be permitted development (no planning) but absolutely needs Building Regulations approval. A change of paint colour needs neither. A large extension may need both. Never tell a customer "you don't need planning, so you're fine" — the Building Regulations question is separate and almost always live. See planning permission and permitted development rights.

Notifiable work and the two compliance routes

Most building work is notifiable, meaning the authorities must know about it. There are two routes to satisfy that:

1. Building Control. You make an application before starting:

2. Competent Person Scheme self-certification. For certain types of work, a registered installer can certify their own work as compliant without a separate Building Control application — and the scheme notifies the local authority and arranges the certificate. The main schemes relevant to trades:

If you do notifiable work and you are not registered with the relevant scheme, you must notify Building Control instead — you cannot simply skip it. Unnotified work leaves the customer without a certificate and with a problem at resale.

The Approved Documents — how to actually comply

Each Part is backed by an Approved Document that translates the legal requirement into practical, buildable guidance — dimensions, U-values, fire ratings, detailing. They are free to download and they are the working reference for the trade. Two points:

  1. Following the relevant Approved Document is the standard accepted route to compliance. If you build to the AD and the inspector agrees you have, you have complied.
  2. The AD is not the only route — the regulations set the requirement, and you can meet it another way (for example, a structural engineer's calculations rather than the AD's standard tables). But departing from the AD means you carry the burden of demonstrating compliance some other way.

The Approved Documents are revised periodically — particularly Parts L, F and O around energy and ventilation — so always work from the current edition and check for transitional arrangements when a new version comes in.

What happens if work is not compliant or not notified

Building Regulations are enforceable. If work does not comply, the local authority can require it to be corrected or removed, and there are enforcement and prosecution powers. Just as common in practice is the resale problem: unnotified or uncertified work — a rewire with no certificate, an extension never signed off, a boiler swap with no Gas Safe notification — surfaces during a property sale and stalls it. The remedies are a Regularisation Certificate (applying to the local authority to assess and certify past work after the event, often involving opening up to inspect) or, in some cases, indemnity insurance — both of which are slower and more expensive than doing it properly first time. Advise customers that "no certificate" is a real liability, not a paperwork technicality.

Frequently Asked Questions

What's the difference between Building Regulations and planning permission?

They are two separate legal systems. Planning permission controls the principle of development — what you build, where, how big, how it looks, its use and its impact on the area. Building Regulations control the technical standard of the construction — structure, fire safety, drainage, insulation, ventilation, electrical safety. A job can need planning but not Building Regs, Building Regs but not planning, both, or neither. The common mistake is assuming that because something is permitted development it needs no approvals at all — the Building Regulations question is separate and is almost always relevant.

Do I need to tell Building Control about my work?

Most building work is notifiable, so usually yes — unless you are registered with the relevant Competent Person Scheme and can self-certify. If you are doing notifiable work (an extension, structural alterations, drainage, a boiler swap, a rewire, replacement windows) you must either submit a Building Notice or Full Plans application to Building Control, or — for certain trades — self-certify through a scheme like Gas Safe, NICEIC/NAPIT or FENSA, which notifies the authority for you. Doing notifiable work with neither route covered leaves the customer without a certificate and a problem at resale.

What's the difference between a Building Notice and a Full Plans application?

Both are ways of getting Building Control involved. A Building Notice is quick — you do not submit detailed plans, you just notify and start, and the work is inspected as it goes. It suits small, straightforward jobs, but the risk is that a non-compliance is only caught on site after you have built it. A Full Plans application means detailed drawings and specifications are checked and approved before work begins — slower to start, but it catches problems on paper, which is much safer for anything structural or complex. For extensions and structural work, Full Plans is usually the wiser route.

A customer's previous work was never signed off — what now?

Unnotified past work is a real liability, and it usually surfaces during a sale or remortgage. The main remedy is a Regularisation Certificate: the customer applies to the local authority, which assesses the past work against the regulations — often requiring some opening-up so the hidden elements can be inspected — and, if satisfied, certifies it. In some situations indemnity insurance is used instead, though that does not make the work compliant, it just covers the risk of enforcement. Either way it is slower and costlier than notifying properly at the time — which is the argument for always doing it right first.

Regulations & Standards