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As someone who has recently purchased a property with a spacious garden, you may be considering building an outbuilding to create more storage space or an extra room for your hobbies. However, before you start constructing your dream outbuilding, it is important to understand the UK planning laws and regulations surrounding outbuildings. In this ultimate guide, I will provide you with a comprehensive overview of the planning laws for outbuildings in the UK, so that you can build an outbuilding without the need for planning permission. So how do you  Building Outbuildings without Planning Approval?

Understanding what constitutes an outbuilding or Garden Room

According to the UK planning laws, an outbuilding is any structure that is detached from the main house and is used for a purpose ancillary to the main dwelling. This includes sheds, greenhouses, summerhouses, garages, and workshops. Outbuildings can be used for a variety of purposes, such as storage, relaxation, or work. However, it is important to note that outbuildings cannot be used for permanent residential accommodation.

Do you need planning permission to build an outbuilding?

The good news is that you can build certain types of outbuildings without the need for planning permission, provided that they meet certain criteria. If your outbuilding complies with these criteria, it is considered to be a “permitted development”. However, some types of outbuildings, particularly those that are larger or closer to the boundary of your property, may require planning permission. So you can build Outbuildings without Planning Approval but do read further as there are some common pitfalls.

How big can you build a Garden Room without planning permission?

The size of your shed or outbuilding is one of the most important factors to consider when determining whether you need planning permission. In the UK, you can build a shed without planning permission if it meets the following criteria:

  • The outbuilding is single-storey
  • The outbuilding has a maximum eaves height of 2.5 metres (as measured from the original ground level)
  • The outbuilding has a maximum overall height of 4 metres with a dual-pitched roof, or 3 metres for any other roof type
  • The outbuilding is located at least 2 metres from the boundary of your property

What are the limitations and restrictions for outbuildings?

Even if your outbuilding meets the above criteria for permitted development, there are still some limitations and restrictions that you need to be aware of. For example, the outbuilding cannot take up more than 50% of the total area of land around the original house. You also cannot build an outbuilding in front of the main house.

It is also important to consider the impact that your outbuilding may have on your neighbours. If your outbuilding is likely to cause any harm or nuisance to your neighbours, such as blocking their light or views, you may need to apply for planning permission. Always check with your Architect, don’t leave it to a Builder.

Building regulations for outbuildings

In addition to planning permission, you may also need to comply with building regulations when constructing an outbuilding. Building regulations ensure that your outbuilding is safe, energy-efficient, and structurally sound. The specific building regulations that apply to your outbuilding will depend on its size, use, and location. For example, if you plan to use your outbuilding as a workshop or studio, you may need to comply with additional regulations to ensure that it is safe for use. We recommend you get Building Regulations approval, but it’s only mandatory above 15sqm for a garden room if its closer than 1m or the foundations are in proximity to another building. Otherwise its 30 sqm typically for buildings (this was an update from Ian Ross at Assure Building Control, thanks Ian ). 

Types of outbuildings – prefab outbuildings and their regulations

Prefab outbuildings, also known as modular buildings, are becoming increasingly popular due to their affordability and ease of construction. However, it is important to note that prefab outbuildings are subject to the same planning laws and regulations as traditional outbuildings. If you plan to build a prefab outbuilding, you will need to ensure that it meets the same criteria for permitted development as a traditional outbuilding.

We recommend getting your Architect to submit and apply for a Certificate of Lawfulness via a Permitted Development application. This is not approval but the Council agreeing formally that the design meets the criterion of Permitted Development.

Why is Getting a Certificate of Lawfulness Important?

Two reasons;

  1. When your Builder builds it, you know any complaints from neighbours will not impact your build.
  2. When you sell the property, the Lawyer will ask if you have planning approval or a certificate of lawfulness for any changes to the house. If this is not available then no one knows if the changes are lawful. That’s when a buyer needs indemnity insurance to buy your house, it may delay or block a sale.

How to apply for planning permission for outbuildings

If your outbuilding does not meet the criteria for permitted development, or if you are unsure whether you need planning permission, you will need to apply to your local planning authority for permission. The application process can be lengthy and complex, so it is important to seek professional advice before submitting your application. When applying for planning permission, you will need to provide detailed plans of your outbuilding, as well as information on its size, location, and intended use.

What to do if your outbuilding doesn’t comply with planning laws

If you have already built an outbuilding that does not comply with the UK planning laws, you may be required to take corrective action. This could include applying for retrospective planning permission or modifying the outbuilding to bring it into compliance. In some cases, you may even be required to remove the outbuilding entirely. It is important to seek professional advice if you find yourself in this situation, as failure to comply with planning laws can result in fines and legal action.

Conclusion and key takeaways

Building an outbuilding can be a great way to create more space and add value to your property. However, it is important to understand the UK planning laws and regulations surrounding outbuildings before you start construction. By following the criteria for permitted development and complying with building regulations, you can build an outbuilding without the need for planning permission. If you are unsure about the laws and regulations surrounding outbuildings, it is important to seek professional advice to ensure that your outbuilding is safe, legal, and compliant.

Need Help?

Have you built an outbuilding that doesn’t comply with UK planning laws? Don’t panic – our team of experts can help you navigate the complex planning laws and regulations to ensure that your outbuilding is safe and compliant. Contact us today to discuss your situation and find out how we can help.

Call Gordon on 02089546291 or email [email protected]

Read more on Permitted Developmen


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Post Author: Gordon evans