The Granny Annexe: Householder or Mobile Home Application?

NAPC often use a dual application approach when applying for planning permission for a granny annexe. The dual application consists of submitting a Householder planning application and applying for a Certificate of Lawfulness for a Mobile Home. But what does this mean? Does your granny annexe fall under the definition of a Mobile Home?

Find out in this blog the differences between the two applications.

What type of Planning Permission do you need for a Granny Annexe?

In all cases, you will need to obtain planning permission for a granny annexe. Permitted development isn’t suitable for annexes as there are limitations on what you would be able to use the structure for.

We often use the Householder Application route to apply for permission for a granny annexe, this is generally the most straightforward and robust method.

In other cases, such as those where it looks highly unlikely planning permission will be granted, we use the Caravan Act to gain a Certificate of Lawfulness for the siting of a mobile home.

However, we often find that the dual application is our most successful approach to gaining planning permission for a granny annexe.

Certificate of Lawfulness

The Certificate of Lawfulness is based on the siting of a mobile home, which is assembled in a very specific way to meet the definition of a caravan.  This does not result in operational development as it meets the definition of a caravan and used ancillary to the main dwelling, does not result in a change of use either. The Certificate of Lawfulness seeks confirmation of that.

It is extremely important to check whether your Granny Annexe can be built under the definition of a mobile home. There is a lot of conflicting and incorrect information relating to the Caravan Act out there. Even if you have been told that your structure meets the definition of a Mobile Home by a provider, we would always recommend talking to a Specialist Planning Consultant for advice.

If your proposal does meet the definition of a mobile home, we would suggest regularising the development by gaining a Certificate of Lawfulness from your Local Planning Authority to ensure the proposal is lawful.

NAPC can provide a robust assessment and collate supporting evidence to support a Certificate of Lawfulness application to your Local Planning Authority.

Householder Application

The householder application is for an annexe which is built using traditional building methods, not in the same way as the mobile home, resulting in development and the need for a Householder Application.

Householder applications are assessed against National and Local Planning Policy and are consulted on with neighbours and the Local Parish Council and relevant Consultees such as ecology, highways heritage etc.

NAPC will provide a thorough planning assessment of your site and accompany your submission with a robust Planning Statement justifying the proposal against planning policies and relevant case law.

Dual Approach

If your Granny Annexe is capable of being built as a mobile home and using traditional building methods, we would recommend submitting a Householder and Certificate of Lawfulness application.

Using a dual approach ultimately gives you two chances of success and the applications can work alongside each other to ensure we reach your desired outcome.

NAPC can provide initial advice if you are unsure what permission you require or whether your proposals would be best suited to a dual approach. Get in touch to discuss your project and we would be happy to help.

An example of when not to trust your own opinion on a mobile home and always regularize development using a Specialist Planning Consultant… like NAPC ????

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Get an answer quicker with a Feasibility Study

A one-off Feasibility Study (from £99) will equip you with crucial planning insight about the area you’re planning to site your Annexe or Garden Room. So if you pursue your application, you have the best chance of success. 

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Annexes are now a popular addition to many family homes to provide additional accommodation.

Mobile Home

NAPC provide a service to help you establish whether your mobile home meets the definition of a caravan and can apply for a Certificate of Lawfulness

Garden Room

Looking to install a garden room at your property? Unsure about planning permission or building regulations for garden rooms?

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