The short answer: probably not
One of the most common questions we hear from homeowners is whether they need planning permission before building a garden room. The good news is that most garden rooms fall within permitted development rights, meaning you won’t need to submit a planning application at all.
We’ve installed over 1,000 garden rooms across South East London, Kent, Surrey and Sussex since 2004, and the vast majority have been built under permitted development. But there are rules you need to follow, and getting them wrong can cause problems down the line.
What counts as permitted development?
Your garden room qualifies as permitted development if it meets all of these conditions:
- Height: No more than 2.5m at the eaves if within 2m of a boundary. Single-storey only.
- Coverage: The garden room, together with any other outbuildings, must not cover more than 50% of the total garden area.
- Location: It must be in the rear garden, not in front of the principal elevation of your house.
- Use: It must be incidental to the enjoyment of the house. That means home offices, gyms, studios and hobby rooms are all fine.
- Listed buildings: If your home is listed, you will always need planning permission.
- Conservation areas: Tighter rules apply. No outbuildings to the side of the house, and total floor area is limited to 10 square metres.
All of our standard and bespoke garden rooms are designed to comply with these rules. During your initial consultation, we’ll check your specific situation and let you know if anything needs attention.
What about building regulations?
Building regulations and planning permission are two separate things. Most garden rooms under 15 square metres don’t need building regulations approval, and those between 15 and 30 square metres are also generally exempt as long as they’re more than 1m from any boundary.
That said, our buildings are engineered to meet or exceed building regulation standards regardless. We use 100mm PIR insulation panels, EPDM rubber roofing, and proper electrical installations carried out by qualified electricians. You can read more about our approach to planning and building regulations.
When would you need planning permission?
You’ll need to submit a planning application if:
- Your property is a listed building
- You live in a conservation area and the building exceeds 10 square metres
- The garden room would be higher than 2.5m within 2m of a boundary
- Total outbuilding coverage would exceed 50% of your garden
- You want to use it as a separate dwelling (in which case, have a look at our granny annexe buildings)
If you do need planning permission, don’t worry. We handle applications regularly and can manage the process for you.
Can I sleep in my garden room?
A garden room used as permitted development must be “incidental” to the main house. Using it as a self-contained bedroom or letting it out on Airbnb would not count as incidental use. If you’re looking for a building you can sleep in, our granny annexe range is designed exactly for that purpose and includes full planning and building regulations applications.
How we can help
Every project starts with a free consultation where we’ll visit your property, discuss your requirements, and confirm the planning position for your specific situation. We’ve been doing this since 2004, so there aren’t many scenarios we haven’t seen before.
Have a look at our standard building range or bespoke options, or give us a call on 01689 818 400 to chat through your project.
Save £5,000 with our Ambassador Programme
We’re currently offering £5,000 off your garden room through our Ambassador Programme. Allow us to photograph your completed build and host up to 3 visits from prospective customers (by appointment only), and we’ll take £5,000 off the price. Find out more.