While you may have exciting plans for a Grand Designs scheme, it’s essential your home extension conforms with Building Regulations. These set national minimum standards for construction from structural stability of walls and roofs to fire safety and ventilation. The rules are enforced by local authority building control departments to ensure the safety of people in and around your property as well as energy conservation. They also protect against cowboy builders.

What’s the difference between Building Regulations and Planning Permission?

Planning permission controls if you can build or alter a property. The rules consider impact on neighbouring properties, landscape considerations, highway safety and the look of your extension.

Building Regulations control how you build or make changes to a property so it conforms to the latest standards of safety and workmanship and is signed-off by building inspectors.

A home extension might require separate permissions for both from the local authority planning department. For smaller schemes, such as internal alterations, only Building Regulations approval may be needed.

It’s important to check how your home improvement project is affected by Building Regulations before you get started. Ask your local planning authority or architect for advice.

Alexander Design - New kitchen with feature glass wall

How do you apply for Building Regulations?

Applying for Building regulations is different to making an application for planning permission. More detailed drawings and notes on how the extension is to be built are required. The drawings must identify the materials to be used and compliance with all the relevant Building Regulations and other legal requirements. Most people will need to hire someone with the technical expertise to produce the drawings and documentation required.

Use this website to find building surveyors, structural engineers, architects, architectural technicians and other experts in your local area (link)

If you are employing a building contractor, it’s usually their responsibility to make sure everything complies but you must check this with them at the start of the project. A local authority or approved inspector will make site visits and check different stages of the construction. If the inspector finds work doesn’t meet regulations, they will usually give you a chance to fix it. A certificate is issued if it passes.

If your home extension remains non-compliant, you can be prosecuted and fined. Your local authority can also make you pay to have the faulty work fixed. And when you come to sell, it can cause problems if no completion/final certificate was issued.

In addition to structural stability, Individual elements of a home extension also need to meet building regulations, including doors, windows, stairs, electrics, kitchens and bathrooms.

Tradespeople who are registered with Competent Person Schemes can self-certify that their work complies with the regulations, for example window-fitters.  They should issue you with a certificate within about two months of completion.