One of the questions people usually ask when looking at putting an office, studio, gym, sauna or other building in their back garden is ‘Do I need planning permission for a garden room?’.
The rules do change over time, and they also vary between England/Wales, Scotland and Northern Ireland, but as of January 2024, the answer is ‘probably not, but it will depend…’.
Outbuildings such as sheds, games rooms, garden offices, music studios, home gyms, yoga studios, and garages will normally fall within what is called “permitted development”, and may therefore not need planning permission. You might reasonably feel that the whole system is more about what’s not permitted!
There are several constraints that apply. The rules for England and Wales are:-
- You may not build so that any part of the new outbuilding is in front of the principal elevation of your existing house. So your new garden office or studio can only be sited at the side or rear of your house.
- The building can only be single storey, with the eaves height a maximum of 2.5 metres.
- If the roof has a dual pitch, the overall ridge height may be up to 4 metres from the ground (as long as the building is at least 2m from any boundary, or the existing house).
- If the roof is a single pitch (or virtually flat), then the overall height must not be more than 3 metres. Bear in mind that this includes any foundations that might be needed.
- If you want to site the building any closer to a boundary than 2 metres, then the overall height cannot be more than 2.5 metres.
- You are not allowed to have verandas, balconies or raised platforms (a platform must not be higher than 30cm).
- Be careful that no more than half the area of land around the “original house” is going to be covered by additions or other buildings. Original house means the house as it was first built or as it stood on 1 July 1948, if it was built before that date. Although you may not have built a shed or an extension to the house, a previous owner may have done so.
- If you are in a “designated area” – i.e. an Area of Outstanding Natural Beauty, a conservation area, a national park, the Norfolk Broads, or a World Heritage site then the maximum area to be covered by buildings, enclosures, containers and pools more than 20 metres from the house is limited to 10 square metres.
- In these “designated areas”, then buildings, enclosures, containers and pools at the side of your house will require planning permission.
- If you live in a listed building, then any outbuilding within its curtilage will require planning permission.
Please note: The permitted development allowances described here apply to houses and not to:
- Flats and maisonettes
- Converted houses or houses created through permitted development rights to change use
- Other buildings
- Areas where there may be a planning condition, Article 4 Direction or other restriction that limits permitted development rights.
Other rules relate to the erection of a new dwelling (i.e. a building that someone will live in – and annexes, or places for dependent relatives to stay etc. will fit into this category).
Once you have been through this, if you are still unsure if your planned building falls into the category of ‘outbuildings’, or if you are unsure if planning permission is required, please contact your local planning authority. Although we have lots of experience with our clients’ projects, we aren’t planning experts!
For full technical details, there is a 50-page document on permitted development available in this UK government guidance (you can browse it online or download it).
If you live in Scotland, the permitted development rules are a little different – you can check out the details here and here.