5 Frequently Asked Questions About Granny Annexe Planning

After posting on our socials, we received the following questions on annexe planning.

1. How Long Does Planning Application for an annexe take?

Usually the planning application process will take 8-10 weeks from the validation period.

We’ve written a step by step guide on how your application will progress below, but in short these are the steps taken to reach a decision.

  1. Pre- Application
  2. Application and Submission
  3. Validation
  4. Consultation and Publicity
  5. Site Visit
  6. Consideration of Application
  7. Recommendation
  8. Decision

Between Weeks 1-3 – Your LPA will write to the statutory consultees to ensure they’re aware of the proposed plans.

This could be the parish council, neighbours, highways and water agency and ward councillors.

They will then have 21 days from validation to submit any comments.

Between Weeks 4-8 a case officer from your Local Planning Authority will look after your case up to the target decision date. This will be at the end of the 8 weeks and usually during this time a site visit will be conducted.


2. How much are application fees?

Application fees will vary depending on what you’re applying for. In most of our cases, this would be either an annexe or mobile home application.

For an annexe, the fee would be £238.20 and the fee for a mobile home would be £135.20. These are both including the planning portal surcharge.

It would be the applicant’s responsibility to pay this directly to their Local Planning Authority.

3. If my building is within 2m of a boundary – how high can it be?

The answer is 2.5metres!

4.I want sleeping accommodation in my garden room, do I require planning permission?

Yes! As soon as you introduce sleeping accommodation into your garden room proposal, it no longer benefits from Class E permitted development.

Home Gyms, Cinema’s, Home Offices or Work spaces ultise permitted development rights, so therefore do not require planning but an annexe is different.

Well whys that? This is due to the fact it’s no longer considered incidental, one of the requirements for PD, it is now ancillary.

5.What can I do to give my annexe application the best chance of success?
  • Ensure the annexe is not located too far from the main house


  • The annexe is not too big and remains subservient to the main house


  • The level of facilities contained within the annexe are basic to ensure it remains ancillary


  • The annexe is located in an area of your garden that won’t negatively impact neighbours privacy and amenity


  • Make sure the design and materials used are in keeping with the surrounding vernacular

If there is a question you would like us to answer, please do not hesitate to contact NAPC with the below contact form.


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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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Book a call with one of our planning experts or call/email us directly.

Phone number

01285 283200



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