A Guide.

In the UK, garden rooms are an increasingly popular addition to homes, providing valuable extra space for various purposes such as home offices and gyms, as well as boosting property value (read Read 5 ways a garden room adds value to your home in Kent for more on this!).

One of the most common questions we get at the Garden House Company is whether you need planning permission for a garden room. That depends…

The size, location and purpose of your future garden room all determine your need for planning permission. Generally speaking, most garden rooms under 2.5m in height (like all of ours!) do not need planning permission, as they are seen as outbuildings. However, there are key exceptions – let’s take a look.

Do I need planning permission for a garden room?

If you have permitted development rights for your home or the area you live in, you generally don’t need planning permission for your garden room.

Garden rooms are classed as ‘outbuildings’ and can be built on your property without permission as long as you comply with permitted development guidelines and building regulations.

Like we said earlier, if your garden room is under 2.5m in height, you’re probably in the clear! However, it’s worth taking a look at the full guidelines to make sure you’re within the rules. Keep reading to find out when a garden room needs planning permission or view the full technical government guidance on permitted development rights.

When does a garden room need planning permission?

Garden rooms do not always fall under permitted development rights, in which case you will need planning permission. You might not have permitted development rights if your garden room will:

  • Be in front of your home or closer to a public road or footpath than the property itself

  • Cover more than 50% of the total area of land around the original house

  • Have an overall height greater than 4m for a dual-pitched roof or 3m for any other roof type

  • Have a veranda, balcony, or raised platform

  • Be used for sleeping accommodation

  • Be built on the grounds of a listed building

  • Be built in a National Park, the Broads, a World Heritage Site, Area of Natural Beauty (AONB) or conservation area and sit between the side of your house and the boundary of the property

Additionally, permitted development rights do not apply if you live in a flat, maisonette or converted house.
Special considerations for homes not under permitted development

If any of the points above sound familiar for your garden room, you will need to apply for planning permission.

There are special considerations for planning permission depending on the type of property you have.

Listed buildings

If you live in a listed building, you will require full planning permission for any structural changes. If you are planning to build a structure that is attached to your main building, you will also need listed building consent.

Designated land
Designated land includes National Parks, Areas of Outstanding Natural Beauty (AONBs), World Heritage Sites or conservation areas.
For all of these, except conservation areas, you can build a garden room without planning permission if your garden room is located more than 20m from your main building and is less than 10m x 10m in size.
 

However, you cannot build a garden room to the side of your property without planning permission. 

Do you need different planning permission for different garden room uses?

You may need planning permission if you will be using your garden room for things you’d do in your main home, like cooking, sleeping or showering.

Permitted development rights cover outbuildings which are ‘incidental’ to the main dwelling – basically meaning spaces which don’t add much further use on top of what your house already offers.

Do you need planning permission for an annexe? 

The rules here are the same as for other garden rooms – you will not need planning permission provided that you or anyone else doesn’t intend to live there.

According to Hastings Borough Council’s website, “An annexe cannot be used to create a new dwelling, independent of the main house. So you cannot rent out or sell the annexe without obtaining planning permission first.” Pretty clear!

Do you need planning permission for a garden office? 

As long as your garden office is under permitted development rights, then you will likely not need planning permission.

However, if you’ll be doing things like meeting with clients or hosting appointments at your garden office, then this may be classed as ‘non-incidental’ and extra to the use of your main house (not to mention impacting the neighbours). In this case, the council may ask you to apply for planning permission.

Do you need planning permission for a garden shed?

In most cases, you don’t need planning permission for a garden shed, as they fall under permitted development rights. Unless you have a particularly small garden, building a shed shouldn’t pose any real problems.

However, if you’re lucky enough to own a bit of woodland, you may want to have a shed to house your tools. In this case, you should seek planning permission.

How to seek planning permission for your garden room

If you do need planning permission for your garden room, don’t let that put you off! With a bit of organisation, you can still build your dream outdoor space.

Each local district council in the UK has their own planning application process, but all of them require the same documents:

  1. Drawings and plans of the garden room
  2. A site location plan
  3. A short description of the proposed garden room

Garden room planning permission applications in Kent & West Sussex

The Kent and West Sussex council websites have their own planning permission application portals to create, track and manage your application, which you can find at Kent County Council planning applications and West Sussex County Council planning applications.

Before you submit a formal application, the councils advise you to pay for their pre-application service. This service helps identify how local planning policies and other factors affect your proposal, as well as if any specialist input will be needed (for example listed buildings).

To increase the likelihood of a successful application and avoid the cost of an unsuccessful application, we recommend you use the pre-application service or consult a local expert in planning permissions who can do the same job. The Garden House Company offers a planning consultancy service to do just that!

Navigating Planning Permission for Your Kent Garden Room

Navigating planning permission for a garden room in the UK can be daunting. However, with the guidelines and considerations outlined above, you’re in a good place to begin designing your dream outdoor space.

At the Garden House Company, our garden rooms don’t usually require any planning permission. But if you do need it, our experts are experienced in planning permission and offer a full architectural design and planning service to help you through the application process. Book your consultation today!

FAQs

You can build right up to the boundary if the garden room has a floor area of under 15m square metres. If your garden room is between 15 – 30 square metres, it needs to be 1m away from the boundary.

If you didn’t need to apply for planning permission, then your neighbours have no right to object to your garden room. If you did require planning permission, then your neighbours will be notified during planning and allowed to object to it.

Garden rooms do not need planning permission if they fall under permitted development and will not be used for activities you’d usually do in your main house, like cooking, sleeping and showering. If you plan to have a toilet or bathroom in your garden house, it’s worth getting more advice for your specific circumstance.

A garden room planning permission application in England costs £258 as of 2024 according to BuildIt, with different costs for garden rooms with special considerations, like listed buildings or within designated areas. You can calculate your exact planning fee with Planning Portal’s fee calculator.