Do I need Planning Permission for a Granny Annex?


The Featured Image is a recent build from Into The Garden Room

Whether housing your grown child as they save to buy their own home or perhaps giving an elderly relative a place to maintain their independence whilst getting more support, an annexe can be a great addition to your home. Certainly, one of the most asked questions when building an annexe is probably whether or not you will need planning permission. Before you grab all the equipment and don your safety helmet, we look at some things to consider when constructing your annexe.

What is an Annexe?

An annexe is a self-contained unit, sometimes referred to as a granny flat. Situated on the same plot as the existing property, the annexe is used as part of the same house. An annexe can be built as an extension to the existing property or as a stand-alone building. The most important thing to appreciate is that an annexe is not a separate dwelling. An annexe is not intended to be rented out for example.

Do I Need Planning Permission?

The quick answer is yes. Whilst garden rooms can often be exempt from planning permission requirements, an annexe, because it is used as a dwelling or living space, will require planning permission or a Certificate of Lawfulness from your Local Planning `Authority (LPA). The LPA will make consideration regarding the impact your proposed annexe will have on your neighbours. They will also consider the surrounding land and including how the structure would look.

How long does Planning Permission usually take?

The great news here is that all Local Planning Authorities sing from essentially the same song sheet. This means that once you have finalised the annexe's proposed design and submit that precious planning permission application, you can expect to wait no longer than approximately 8 weeks for a decision. If you do decide to use a company to submit all the paperwork, they will stay in close contact with the LPA and keep you informed along the way.

Can You Use the Caravan Act to Build the Annexe?

You may be familiar with The Caravan Act as another way to build your annexe and avoid the lengthier process of requesting planning permission, but the truth is it is not as easy as that. The Caravan Sites Act 1968 does allow for the construction of certain types of buildings without using planning permission; however, there are quite strict guidelines to follow. A rough outline of the major criteria in regards to the Caravan Act are:

  • Maximum dimensions

  • 65.6’L x 22.3’W x 10’H

  • Must be a structure rather than a building

  • Must be fit for human dwelling

  • Must be able to be moved from one place to another

The below image is a Bespoke Tiny Home Container Conversion by Crossan Container Conversions, who specialise in movable solutions, which means that should you move the building can be moved. Because it is a movable solution, it may fall under the caravan act. So, whilst the Act can be used to support the build of your granny annexe, we would always recommend applying for planning permission or a Certificate of Lawfulness rather than ploughing money into a project you later find out isn't lawful. We hope this has been informative and helped you to understand the requirements for your very own granny annexe; you can start a search for your very own annexe here.


Planning Permission
Granny Annex

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