Building Regulations — When You Need Approval and What Inspectors Check

What Are Building Regulations?

Building regulations are a set of statutory minimum standards that all building work in England and Wales must meet. They cover structural integrity, fire safety, energy efficiency, drainage, ventilation, electrical safety, and accessibility. Unlike planning permission — which controls whether you can build — building regulations control how you build.

Most significant building work requires building regulations approval, regardless of whether it also needs planning permission.

What Do Building Regulations Cover?

The regulations are divided into Parts, each covering a different area:

• **Part A — Structure:** Foundations, walls, floors, roofs must be structurally sound
• **Part B — Fire safety:** Means of escape, fire spread between dwellings
• **Part C — Site preparation and moisture resistance**
• **Part E — Sound insulation:** Between properties in conversions
• **Part F — Ventilation**
• **Part L — Conservation of fuel and power:** Insulation and energy standards
• **Part P — Electrical safety:** All notifiable electrical work must be carried out by a competent person or inspected by building control
• **Part J — Combustion appliances:** Boilers, wood burners, flues

When Do You Need Building Regulations Approval?

You need approval for:

• Extensions (all types)
• Loft conversions
• Garage conversions
• New windows or doors replacing existing ones (unless the installer is FENSA registered)
• New electrical circuits
• Boiler replacements or new heating systems
• Structural alterations (removing a load-bearing wall)
• Converting a house into flats
• Adding a new bathroom or WC in certain positions

You generally do not need approval for: like-for-like repairs, minor works such as fitting kitchen units, painting and decorating.

Types of Building Regulations Application

Full Plans Application

You submit detailed drawings before work starts. Building control checks them and issues an approval notice. Inspections are carried out at key stages during construction. A completion certificate is issued when all work is signed off.

**Advantage:** You know in advance that your design meets the regulations, reducing the risk of costly changes on site.

Building Notice

A simpler route where you give notice that work is about to start, without submitting full drawings. Building control will inspect during construction and raise any issues on site.

**Advantage:** Faster to start. **Disadvantage:** No upfront check — you may be asked to redo work if it does not comply.

The Inspection Process

At key stages — foundation excavations, damp-proof course, structural elements, roof, insulation, drainage — the building inspector will visit and check the work. You are responsible for notifying them at the right time.

The Completion Certificate

Once all work is finished and inspected, building control will issue a **completion certificate**. This is one of the most important documents you can have for a property. It confirms that the work was carried out to the required standard.

Without a completion certificate:

• Future buyers’ solicitors will flag the works in their enquiries
• Mortgage lenders may require indemnity insurance before lending
• The work may need to be exposed and re-inspected at your cost

Selling Without Building Regulations Sign-Off

If you sell a property where building work was done without approval — or without a completion certificate — your solicitor will need to declare this. The buyer’s solicitor will typically request either retrospective regularisation or an indemnity insurance policy.

Indemnity insurance is a one-off premium (typically £100–£500 for residential works) that protects the buyer against enforcement action. It does not confirm the work was safe — only that the buyer is financially protected. Where safety is a concern, regularisation is the correct route.

Store your completion certificate in your Property Passport as soon as it is issued.