How it works

The Building Regulations – a set of 14 statutory documents Part A to P – on their own won’t ensure your project is perfect. You will still need to hire experts like an architect or structural engineer to turn your dream extension into reality. These professionals have in-depth knowledge of building regulations and will design your extension or conversion in accordance with them.

In England and Wales, you can apply for building regulations approval from either the building control department of your local authority or a private approved inspector who will tell your local council about the work. It is up to you which building control body you choose. However, only councils have powers of enforcement. In Scotland, building regulations, known as building standards, are still only administered and enforced by local planning authorities.

Do I need to apply?

Some smaller home improvement projects are generally exempt, such as replacement baths, sinks, basins and toilets. But home extensions, conversions and renovations are legally required to get building regulations approval - even if they don’t need planning permission. You can delegate this duty to your building contractor or architect but ultimately, it’s your responsibility to ensure your home complies with the rules and regulations.

Routes to building regulations approval

For larger projects, a ‘full plans’ application can be submitted before work is carried out. This needs to include a completed application form, fee and a detailed set of plans – floor plans, elevations and sections – with enough information to explain how the proposed work complies with all the relevant building standards. Structural calculations and technical drawings may also be needed. For example, any work that involves the removal of a load-bearing wall to create a big, open-plan space.

The building control body will scrutinise the plans and perhaps ask for additional information or amendments before issuing a formal notice of approval. This gives peace of mind that so long as your builder sticks to these plans, building regulations will be met.

The other way to obtain approval is called a ‘building notice’. In these cases, no plans need to be submitted, all that is required is a completed application form and fee. Building notices are typically used for smaller projects. With either route, a building control inspector will make site visits at key stages to check the work meets the regulations, for example laying of foundations.

Full plans or building notice?

It is up to you to decide which to choose. One advantage of a building notice is speed – you can start work two days after your notice has been submitted to the building control body. By comparison, it can take 5-8 weeks for full plans to be processed by a local authority. But the downside is that you don’t get a formal notice of approval like you do with full plans. So, there is a risk that completed works might not be approved. Remedial work may need to be done to expose structures, inspect the work and redo it so it complies with regulations. This can be expensive and frustrating.

So, while a building notice may initially save money as you don’t need any technical drawings or plans to accompany the application, it may result in extra cost and delay further down the line. Plus, a detailed set of drawings for your builder to follow reduces problems on site and makes it easier to calculate costs.

Fees and costs

Local authority building control teams base their fees on the cost of their work, such as site inspections. Fees vary from council to council. But as a rough guide some local authorities charge around £100 for a full plan application and a further £200-400 for inspections. Private inspectors negotiate their fees directly with you, usually around 1-2% of the total construction cost.

Competent Person Schemes

For certain jobs, tradespeople who belong to a competent person scheme can self-certify their work meets building regulations. This means you don’t have to pay for a local council or private building inspector to check their work. An installer registered with a competent person scheme is qualified to carry out specific types of work in accordance with the rules. If necessary, they will tell your local authority about the work on your behalf. They’ll also give you a certificate within eight weeks of completion as evidence of compliance.

The main schemes include APHC (plumbers), BESCA (electricians), Fensa and CERTAS (window and door installers and NAPI (replacement roof coverings) but there are many more. For a comprehensive list of the authorised schemes see this government website. 

Why your project must comply

If you fail to notify building control about your project, or the council finds it isn’t up to standard, it has powers to order you to pull it down or alter the work. Serious cases of failure to comply can result in prosecution. If you are convicted, you could face a fine of up to £5,000 for each offence plus £50 for each day the work remains uncorrected. The local authority can also make you pay for the faulty work to be fixed.

Most importantly, if your project doesn’t comply it may be unsafe or could cause major health problems, injury or even death. It may not have enough windows for ventilation or to escape a fire or stairs that are a trip hazard, for example. It may also not meet energy efficiency standards.

When it comes to selling your home, a certificate to show the extension or conversion complies with standards is a key piece of paperwork. Your buyer’s mortgage company will want to see the certificate of building regulation completion before the sale goes through. If the work hasn’t been inspected by a building control body, there will be no official records.

It is possible to get retrospective building regulations approval from your local planning authority, known as a ‘Certificate of Regularisation.’ However, this many involve comprehensive remedial work to meet standards – and there is no guarantee the work will be approved.

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