Guide to Extension building regulations 2021

Why not increase the size and value of your property with a home extension? Before you get started though, find out about the relevant UK building regulations for extensions here.

building-regulations-guideThe current economic climate is forcing more people to stay put rather than buy a new property. This can be a problem if you need more space; for example, perhaps you’re having a child or ≈you simply feel you’ve out grown your current home? Whatever the reason, many people are looking to extend their current property in order to get the most from it. Whilst the cost of an extension can be expensive, it’ll certainly add value to your home. However, it is not just a case of contracting a builder to do the work; you need to consider various rules and regulations first.

What is planning permission and why is it necessary?

In most cases you will need a successful application for planning permission before any work is allowed to commence. Planning permission is very important, because it allows your local council to plan for the future and understand how the land is being used. This will have an impact on the appearance of buildings, the general landscape and even things such as road access and environmental implications.

Do I need planning permission?

You will need planning permission if any of the following applies to your extension:

  • The extension is higher than the highest part of your original roof.
  • Any part of the extension is more than four meters high and within two metres of your boundaries.
  • The extension will take up more than half of t he total ground area of your land (this excludes ground covered by the original property).
  • The total volume of the original building will increase by more than 115 cubic metres.
  • The total volume of the original building is increased by more than 10% for terraced houses or any property in a conservation area of national park.

What is the planning process?

Once you have sent your local council your application it will place the plans on the Planning Register for public viewing and they will also notify your neighbours. Your local council will also appoint a committee who will make a decision with regards to the planning application. This decision can take up to eight weeks to be made and if you are granted permission you must have the proposed work completed within five years. If you are denied planning permission you can make amendments and then resubmit within 12 months, without incurring a further charge. You can lodge this appeal within three months of a council’s decision.

What if I fail to get planning permission?

If you go ahead and build an extension without obtaining planning permission first then you could incur a hefty fine. On top of that you may have to demolish your work. You can get more information on planning permission via your local council.
Are there any building regulations?

When extending your house you will need to make sure that you comply with government building regulations. This will apply to you unless your extension falls into one of the following categories:

  • Porch
  • Conservatory
  • Detached garage (built at ground level and taking up less than 30m2 of floor space)

These building extension regulations apply to any building in England or Wales. They aim to set a minimum standard for the design and construction of loft-conversion-newthe building in order to comply with health and safety regulations. There are also extension regulations regarding fuel and power conservation.
Any good builder should be able to help you in making sure that your extension meets all the building regulations that could apply to your property.
How do I comply with building extension regulations?

Building regulation approval is an entirely different entity to planning permission. However it is of upmost importance to ensure that you get both. To achieve compliance with building regulations you (or your architect if you have one) will need to submit very detailed plans on the extension, along with the application and fee to your local planning authority.

Once you have done that they will send out a building control surveyor in order to examine the plans and make sure that they do indeed comply with the building extension regulations. Your builders need to let the council know when the building starts as well as notify at various stages throughout the project. This is so that inspections can be scheduled to make sure work is carried out to a suitable standard. Once you have finished the extension, a final inspection will be carried out and a certificate of completion will be given to you as long as everything is compliant with the extension regulations.

What if there is a dispute regarding the regulations?

If there is a dispute regarding an extension subject to the building regulations and the local authority, then determinations can be used to decide. A determination is made by the Secretary State for Transport (if you are building in England) or the National Assembly (if you are in Wales). They will be able to decide whether or not something adheres to the building regulations. Such disputes can be settled by a determination, but you will need to apply for one as soon as the dispute arises and definitely prior to any considerable construction has taken place.
How much does it cost?

Either contact your local council or a building company for a more detailed cost outline. As a rough guide it would cost you £150 to submit an application for an extension to a single dwelling, including works within boundary.