If you’re considering a garden room with Horto, one question worth knowing is, Do I need planning permission for my garden room? The simple answer is, not always, but the rules are varied and getting them wrong can lead to delays or extra costs that could be avoided.
In this article, we explain about planning permission for garden rooms, how permitted development rights work, and highlight why now, in the warmer, drier months, it is the perfect time to get your project moving.
Why August is a great time to start your garden room project
While planning permission rules don’t change with the seasons, the practicalities of building do. Starting your project in late summer offers you the following advantages:
- Better weather for groundwork and installation: Less chance of rain delays.
- Faster completion times: Suppliers and installers can often work more efficiently in drier conditions.
- A head start for autumn/winter use: If you plan now, your garden room can be ready and fully functional during the colder months.
- Availability before the spring rush: Demand typically spikes in spring, so acting now can help you avoid long lead times.
And if your project does require planning permission, you’ll have time to get the paperwork sorted.
What is planning permission?
Planning permission is formal consent from your local authority to carry out certain types of building work or change how a property is used. It ensures developments are in keeping with local planning policy and won’t negatively affect neighbours or the environment.
Whether you need planning permission for garden rooms and other outbuildings depends on the size, location, height, and intended use.
Permitted development rights
Many garden rooms can be built without planning permission thanks to permitted development rights. These are rules that allow certain building works and changes without the need for a full planning application.
If your garden room falls within these guidelines, you can skip the application process entirely. But you’ll still need to ensure your design complies as your local council has the authority to ask for changes if it doesn’t.
Key rules for garden rooms under permitted development
For most homes in England, the main criteria for permitted development are:
- Location: The garden room must be in the rear or side garden, not in front of your house and it can’t extend beyond the front wall of your property.
- Size and coverage: Outbuildings (including sheds, garages, and the proposed garden room) must not cover more than 50% of the total land around the “original house” (how it stood in 1948). If you’ve already extended your home, the allowable area may be reduced.
- Height limits: The maximum overall height of your garden room should be 4 metres for dual-pitched roofs and 3 metres for any other roof type and the maximum eaves height should be 2.5 metres. If the structure is within 2 metres of the boundary, the entire building must be no more than 2.5 metres high.
- Use restrictions: The building must be incidental to the enjoyment of the dwellinghouse, meaning it can’t be a separate home or contain permanent sleeping accommodation. Home offices, studios, gyms, and hobby spaces are fine. Granny annexes or Airbnb units are not.
- Designated land and listed buildings: In conservation areas, National Parks, Areas of Outstanding Natural Beauty (AONB), or World Heritage Sites, stricter rules apply. If your home is listed, you will almost certainly need consent, and the design will be closely examined.
When planning permission is required
You’ll need to make a planning application for your garden room if the following applies:
- Your garden room exceeds the permitted size or height.
- It’s intended as a permanent sleeping accommodation.
- It’s attached to the main house.
- You live in a flat or maisonette (permitted development rights usually don’t apply).
- You want to include balconies, verandas, or raised platforms over 0.3 metres high.
What about Building Regulations?
Aside from planning permission, Building Regulations set standards for safety, energy efficiency, and accessibility. You usually don’t need Building Regulations approval if your garden room is:
- Less than 15m² in floor area.
- Contains no sleeping accommodation.
If it’s between 15m² and 30m² and more than 1 metre from any boundary, or built from non-combustible materials, you might also be exempt.
However, if you plan to add plumbing, electrics, or heating, or use it for sleeping, Building Regulations approval will likely be needed.
Certificates for peace of mind
Even if your garden room meets permitted development criteria, you can apply for a Lawful Development Certificate (LDC). This isn’t mandatory, but it proves the building was legal at the time of construction, which is invaluable if you sell your home later.
Why it’s worth talking to experts early
While the rules seem straightforward, small details can make a big difference, especially around height, boundary distances, and designated land restrictions. A professional garden room provider can:
- Design your space to meet permitted development requirements.
- Liaise with the local council if needed.
- Advise on Building Regulations compliance.
- Save you from costly redesigns or delays.
Horto’s quick checklist
Here’s Horto’s quick checklist, to see if your garden room is likely to be permitted development:
- Behind or beside your house.
- Height no more than 2.5m if within 2 metres of the boundary.
- Not covering more than 50% of your garden.
- Used for non-residential purposes only.
- No raised platforms, balconies, or verandas.
- Not on designated land or a listed building.
If you tick all of these, you’re probably safe, but we would always advise double-checking before you build.
Make the most of the summer window
With the current warm weather and long daylight hours, which are good for construction, August is the ideal time to finalise your design, confirm compliance, and start building. Acting now means:
- You avoid the autumn rush when demand increases.
- Your space will be ready for cosy autumn evenings and festive gatherings.
- Any planning permission, if required, can be handled before winter slows the process down.
By planning in the summer, you give yourself the best chance of a smooth, quick build, ready to enjoy year-round. And if there’s any uncertainty, the team at Horto are happy to guide you through the process from concept to completion, ensuring your new space is beautiful, functional, and fully compliant.