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Granny Annexe Planning: Obtaining Permission to Build

Granny Annexe Planning Permission Made Simple…

Obtaining granny annexe planning permission to build your new granny annexe will certainly put you through a whole range of emotions as you decide whether building an annexe in the back garden is the right thing for you and your family.

We know that every situation is unique and we’ll endeavour to make the journey as smooth and stress free as possible.

Working with your Local Planning Authority

When building a granny annexe, one thing that crops up very early in the decision making process is the daunting prospect of obtaining permission to build a granny annexe in your back garden from your Local Planning Authority (LPA).

Contrary to popular belief, a granny annexe with someone living in it on a day-to-day basis will always need either planning permission or a Certificate of Lawfulness from your LPA.

Some temporary-style buildings such as leisure buildings that are not going to be lived in may not need planning permission.

This is not something you should attempt yourself. It is only something that should be handled by professionals who specialise in obtaining residential planning permission in the UK.

With that in mind, and with a success rate of over 90%, it’s a service we offer to all our iHUS customers because we want your application to be a successful one.

The easiest (and best) way to find out what your chances are of obtaining planning permission for your granny annexe is to book a free on-site consultation service with one of our experts.

They have years of first hand experience of what your Local Planning Authority is likely to approve of and what they are likely to reject.

For example, you may want a pitched roof annexe, but we might advise during our free on site consultation that because the property is overlooked by several neighbours we would recommend a flat roof annexe as your best option.

This kind of precise knowledge and advice is invaluable and can potentially save you hours of wasted time not to mention thousands of pounds in trying to get granny annexe planning permission in the wrong way.

Most garden annexes like those in our HUSCore range are designed for back garden annexe use.

Granny Annexes and the Caravan Act

You might also have heard a lot about the Caravan Act as being a ‘silver bullet’ (it can still be refused), but it will still require a Certificate of Lawfulness from your Local Planning Authority.

We also offer this service as in some circumstances and this may well be your best route to obtaining permission and you have fuller flexibility on the design and size you would like.

When you obtain planning permission to build an annexe in the back garden you are working with your Local Planning Authority to develop the land. They will have input on how it looks, what materials and finishes are being used on the outside, and which style and size they will accept.

With the Caravan Act you are applying to site a temporary building on the land not develop it.

All our granny annexes are classed as mobile homes, so a self contained garden annexe will attract zero-rated VAT, saving you thousands of pounds when compared to a home extension for example.

It’s simple to get the best advice about your granny annexe project and find out the best way to go about obtaining the right type of planning permission for your granny annexe at the same time by requesting one of our informal on site consultations as your very first step to success.

Our annexe experts will discuss with you the best route for obtaining granny annexe planning permission for you and advise on the best location and style for your particular garden.

It’s simple, free, effective and gives you all the right information to help you make the best decision for your family now and for many years to come.

Granny Annexes And Standard Householder’s Planning Applications

For Granny Annexes that we consider to be “straightforward” during our on site consultation (based on many years of building granny annexes of all types throughout the UK) we recommend the normal Householder’s Planning Application route which is the same type of planning permission you would apply for if you were building an extension or adding something to your garden such as a raised decked area.

In some circumstances a Full Application will be requested by some Local Planning Authorities that deem a Granny Annexe to be a new dwelling (this will require a further and significantly higher fee). There seems to be very little consistency with regards to this across Local Planning Authorities even within the same county.

Although the process is a well recognised one, Granny Annexes are not something that your Local Planning Officer may have dealt with before and they are likely to have concerns and questions that we would deal with on your behalf.

Your Local Planning Authority is likely to have concerns over things such as :-

The overall size of the Granny Annexe in relation to the main house and the size of your garden.

The specification of the living accommodation as it needs to be considered ancillary to the main house to be an annexe.

They will want to know the reasons why you want to build an annexe in the back garden, who will be living in it in the near future, and what long terms plans you have for it in the future.

Planning approval will only ever be granted when you fulfil all the requirements of your Local Planning Authority and in particular the concerns raised by the Local Planning Office who is in charge of your application.

The preparation of all the required drawings, application and design and access statements required will be carried out by our planning specialists on your behalf.

All Local Planning Authorities abide by the same timescales when it comes to dealing with your planning application and will more often than not give a decision within the 8 weeks of them validating your submitted planning application.

Why Do Some Granny Annexe Planning Permission Applications Get Refused?

Unfortunately all granny annexe planning permission applications are dealt with on an individual basis and your decision can rest on one particular officer’s opinion on any given day wherever you happen to be within the UK.

UK planning laws are open to interpretation and that means that there are variable factors that can influence your planning application success that are completely out of any one’s control.

In the unlikely event that planning permission is refused we will appeal on your behalf, this can take a further 6 months or more but very few get to that stage without considerable negotiations having been exhausted first by our planning specialists.

Most Local Planning Authorities are more than happy to enter into a very detailed and sometimes lengthy discussion with our planning specialists to make sure the outcome is fair to both parties especially when there is an established need for relative care involved.

Despite popular opinion, they really are there to do a great job at making sure Planning Laws are abided by.

The most frequent reason for refusal we’ve seen to date has been in relation to the annexe size. The few that we have had refused were considered too big for either the plot size or too big to be considered ancillary to the main house.

Granny Annexe Planning Permission And Written Laws And Statements Supporting Them

The provision of granny annexe’s is supported by central Government, Laying the Foundations, A Housing Strategy for England documents which states;

“Planning homes and communities that enable older people to remain economically active, involved with their families, friends and community and able to choose where and how they live not only makes financial sense but also results in a better more inclusive society”

In addition, the National Planning Policy Framework (that your Local Planning Authority adhere to) states:-

2.Sustainable Development

2.1 The National Planning Policy Framework is at the forefront of driving sustainable development in the country, and states that there should be an automatic presumption in favour of sustainable development. Paragraph 14 of the Framework sets out the context within which this presumption should be applied.

2.2 The NPPF puts great weight on considering the local needs, and approving sustainable proposals without delay. The NPPF defines three dimensions to sustainable development:

  • An Economic Role
  • A Social Role
  • An Environmental Role

An Economic Role

2.4 The proposal provides an affordable unit of ancillary accommodation for the applicant’s family members. It also ensures the site is being used efficiently and, in its own small way, bolsters the construction industry.

A Social Role

2.6 The requirement to provide affordable and sustainable accommodation for elderly family members is ever increasing. Age UK published “Care in Crisis 2014” which sets out the very  clear need for flexible accommodation solutions for the elderly:-

  • The number of people aged 85 and over (the group most likely to need care) has increased by 30 per cent between 2005 and 2014.
  • Between 2005/6 and 2010/11 public funding for older people’s social care stagnated.
  • 21% increase of residents in nursing. Residential homes since 2005.
  • From 2010/11 to 2013/14 public funding for older people’s social care (including transfers from the NHS to councils) decreased by 10 per cent in real terms.
  • Councils have cut back on their funding for social care.
  • In 2011, it was estimated that 2 million older people had care related needs.

2.8 “Annexes” can additionally provide ancillary living accommodation for younger members of the family, allowing them to save for deposits for their first home, improve living conditions, provide a measure of independence and allow extended families to stay together.

Local Planning Permission And Neighbours

When a Householder Planning Application is submitted, your neighbours will be notified of the application and be invited to comment or object to the proposal in the normal way.

Your granny annexe planning permission application success does not depend on whether your neighbours object or not, it can only be refused on planning policy.

However if you do have neighbours who might be able to see the annexe or if it invades their privacy or light in some way you may need to take relevant steps suggested by your LPA to make sure the annexe does not affect your neighbours in that way.

It is worth noting that with the Caravan Act your neighbours will not be notified.

Whichever granny annexe planning permission option we deem to be the best for you, it’s always advisable to notify your neighbours in person and explain who the annexe is for and why.

Most people will be supportive of helping a family member and you can then discuss any concerns they might have which will help in the long run.

Your Best Chance Of Success In Obtaining Permission To Build A Granny Annexe In Your Back Garden

  1. Book a free on site consultation with one of our annexe consultations first and get the best free advice you are ever likely to get about annexes anywhere in the UK.
  2. Put your planning application in the hands of professionals. If you try to do this yourself to potentially save money and you get a refusal you will find it 10 times harder to get your application approved at a later date, It’s not worth the risk.
  3. Don’t accept the advice of a “family friend” or even an architect (even a well intentioned one) as to whether or not you will get planning permission for a Granny Annexe, ask us instead, it’s likely we’ve seen a situation similar to the one you have and can advise you accordingly.
  4. Realise that there are no guarantees to getting granny annexe planning permission because of all of the factors listed above and the individual merit of each application. However we have an excellent record of success and have probably built more annexes than any other annexe company in the UK to our credit.


  1. Our free on-site consultation service is the easiest and quickest way to get the right information about planning permission and your granny annexe project.
  2. Obtaining permission from your Local Planning Authority to be able to build an annexe in your back garden is not something that should be tackled by anyone other than an expert in obtaining residential planning permission. (iHUS do this for you as part of our turn-key service)
  3. Our annexe experts will advise you on the best style, position and size for your granny annexe during the on site consultation. It’s worth doing things the right way at the beginning for peace of mind and less stress later in the process.

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Download our iHus annexe brochure

Download our iHus annexe brochure

If you would like to download our annexe brochure, please complete the form below. You can also request for a hard copy to be posted to your home address. Have any further questions, why not request one of our team get in touch?

If you would like to download our annexe brochure, please complete the form below. You can also request for a hard copy to be posted to your home address. Have any further questions, why not request one of our team get in touch?


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      Download our iHus annexe brochure

      If you would like to download our annexe brochure please complete the form below. You can also request for a copy to be posted to your home address. Have any further questions, why not request one of our team get in touch?


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              Download our iHus annexe brochure

              If you would like to download our annexe brochure please complete the form below. You call also request for a copy to be posted to your home address. Have any further questions, why not request one of our team get in touch?

              Download Your Free Annexe Brochure