Granny annex planning permission

Do you need planning permission for a granny annex?

One thing that is only clear when you really delve more deeply into the government sites on planning policy, is that any building where it is intended that someone will sleep should have planning consent obtained. A key point  to consider is that if you build with the wrong permission it can affect the sale of the house in the future. Below are comprehensive answers to your annex planning questions.

Do You Need Planning Permission For A Granny Annex?

'any building where it is intended that someone will sleep
should have planning consent obtained.'

Our planning consultants have kindly consented to thoroughly answering some of the questions that we hear from clients all the time, and we have set the answers out below.

We have separated each section as follows:

  1. Permitted development and certificates of lawfulness.

  2. Planning for annexes.

  3. Other points and conclusion.


1) Permitted development and certificates of lawfulness.

Q. What is the difference and between permitted development, certificate of lawfulness and full planning and why each may be suitable for a garden annex and under what circumstances?

An outbuilding under permitted development must accord with the requirements of Class E of the GPDO (Outbuildings Incidental to the enjoyment of the dwellinghouse). If the unit is considered permitted development, then a certificate of lawfulness application will be submitted to confirm with the council that the development accords with this requirement.

'a garden annex will fall under a householder application
and not permitted development'

However, a garden annex will fall under a householder application and not permitted development, as the unit is not incidental, but rather an extended form of accommodation to the main dwelling. Therefore an application will be submitted.

Q. I would especially like clarification on these points, as over the years we keep hearing them:

a) Is it the case that you need a certificate of lawfulness for an out building of any description in the garden, or can you just build one as long as it falls in permitted development?

A garden outbuilding can be erected under permitted development if it falls within the size and use criteria of the permitted development document Class E. Whilst the document is clear on the size restrictions, the use often remains a grey area. Consequently, it is advised that advice is sought from the council or a planning consultant before proceeding further.

b) Is there a difference for a structure that only provides temporary sleeping - i.e. occasional sleep overs?

This is another grey area in policies!  Some authorities might consider it acceptable under a certificate of lawfulness, but this is very rare. However, we would recommend that for the avoidance of doubt and for the applicant's peace of mind that they apply for an annex under a householder application which would confirm an ancillary use of sleeping accommodation.

c) Can you get permitted development if you put a shower room or for both shower room and kitchenette in? 

The answer to this is covered in point d), below.

d) Is it true that as long as there is a dependence on main residence (i.e. you have to go to the main house to prepare meals) then this falls under permitted development, even if you sleep there?

No. Permitted development for an outbuilding is only acceptable if the unit is incidental to the enjoyment of the dwellinghouse. Incidental uses mean such matters as an office, playroom, garden storage, etc..

This is a very grey area of planning and therefore it is often advised that if we consider there to be an option for permitted development and a certificate of lawfulness, the council is approached before an application is made.

2) Planning for annexes.

Q. Is it easier to get a garden annex planning or a garage extension?

This is unfortunately a question which does not have a simple or direct answer. One is not necessarily easier than the other and will depend on matters such as local context, available garden space and local planning policies.

Traditionally, most councils may seem more welcoming of annexes which form part of an extension to the main dwelling, as the unit is less likely to be considered as an independent dwelling. However, if the local context or the layout of the site does not permit this, then one should not force such a design.

It is also advised that the context of the site is properly reviewed before considerations are made on the best approach.


Q. From a planning point of view, what are the general points that favour a garden annex - i.e., not having road access to the garden, size of annex relative to the house, etc.?

There a number of general points which can help the annex application including:

  • Size - An annex should be clearly subordinate in size to the main dwelling i.e. it must be substantially smaller.

  • Internal layout - having a kitchenette instead of a fully fitted kitchen may help to ensure  further reliance on the main dwelling.

  • Context - The annex should consider its proximity to neighbouring properties.

  • Appearance - The design should take into consideration the surrounding area and context. 

Q. What's involved in the process that you use for getting planning for a garden annex?

We normally begin by reviewing the proposed location of the garden annex and its context.  Common concerns relating to annex applications include: 

  • Overlooking and overshadowing of neighbouring gardens.

  • Size in relation to the existing garden.

  • Access to the garden (are there side gates or other ways to access the garden other than the front door?).

  • Internal layout and items (does it have a kitchen and a bathroom?).

Once a review has been undertaken, we would advise whether any further information might be required or if there are any other known concerns (for example; some councils have policies against the development of annexes).

Provided we see no major concerns, then we would research and write a supporting planning statement and submit the application with the proposed plans.

Throughout the first stage of the application we will engage with the council to ensure the case is correctly validated and that there are no concerning consultation responses (this can take between 4-6 weeks).

'the case officer may ask for minor amendments'

Following the statutory consultation period, we will open discussions with the case officer about the proposal to ensure they understand the scheme correctly and that there are no further concerns.

One matter which applicants should be aware of is that the case officer may ask for minor amendments, such as a reduction in size or the shape of the proposed roof.  This can be quite common and provided these changes can be made, we are normally able to mitigate the majority of concerns before a decision is given.

The whole process from start to finish takes approximately 14-16 weeks.

Q. What happens if planning consent is not given first time?

To answer this question there are two possible scenarios;

1) The decision was unfairly given:
We have had cases where annexes have been refused because the case officer has considered the annex as an independent dwelling application, rather than an ancillary unit. In such cases, and permitted there are no other reasons for refusal which cannot be disputed, we will often advise that the case is taken to a planning appeal and reviewed by an independent Inspector. This process can take up to 6 months and therefore we tend to only suggest this as a last resort.

2) A subjective decision was given:
If the reason for refusal is a more subjective reason, such as design, then we will advise that we engage with the case officer to negotiate on scheme amendments and prepare the case for a re-submission. This process can once again take between 14-16 weeks.

'correspond with the neighbours to ensure they are on board with the scheme.'

Q. What say to the neighbours have in the process?

Neighbours are able to comment on the proposal within the first four weeks after submission. These comments can be negative or positive. Therefore we often advise that before a submission, the applicants try to correspond with the neighbours to ensure they are on board with the scheme.

'flexibility in the design of the annex and the layout are vital'

3) Other points and conclusion.

Q. Do you have any other points that clients should consider?

I think it is important to stress to applicants that throughout a planning application, flexibility in the design of the annex and the layout are vital, as councils will often seek amendments to areas of concern.

In addition, the more information which is provided before an application is submitted the clearer it is for the case officer why the annex is required in the first place. Therefore, the use of personal statements to help reflect one's personal requirement is often a useful supporting tool.

As you can see from the above, there are areas where negotiation and preparation of a solid case for an annex will help towards gaining you a successful outcome. In particular, communication both with your council and neighbours may help the application by including opinions and issues early on, rather than an application coming in cold.

We have found that different councils seem to differ widely in their interpretation on the planning rules, and so, for residential uses of any kind, these should be formally agreed with the planning department in your locality. For your own peace of mind and protection, you are best to be covered with a clear and unambiguous document from your local council.

Please contact us if you have any further questions and we will be happy to help - you can call 01279 755155, or you can use our online enquiry form (click here) if you prefer.


How to obtain Granny annex planning permission.

We are happy to speak with you and discuss your circumstances and options. If you need planning permission, we work with excellent planning consultants who have a very high success rate and will be able to work with you to obtain planning consent.

Over to you... If you have any planning questions or comments on this article, please add them, below.

Last update: 18.10.2018
Posted on August 3, 2016


Quick enquiry

Name (inc surname).


How can we help you?

See our privacy policy for details of how your data is used.

Join our Newsletter

* indicates required

Recent posts

Log cabin interior design
Annexe planning permission
Permitted development
A Hunting lodge: luxury log cabins France
Moving a log cabin