Dreaming of a garden office, a stylish summerhouse, or a practical storage solution? Many homeowners wonder about the boundaries of what they can build without needing formal planning permission. Understanding how big an outbuilding can be without planning permission is crucial for a smooth and stress-free project.
The Permitted Development Puzzle Understanding Outbuilding Size Limits
The question of how big an outbuilding can be without planning permission is governed by what’s known as Permitted Development Rights. These rights allow homeowners to undertake certain building projects without the need to apply for planning permission, as long as they adhere to specific rules. The most significant factor determining the size and placement of your outbuilding under Permitted Development is its proximity to your house and the total area of your garden. It’s incredibly important to get these measurements right to avoid potential enforcement action.
Generally, for an outbuilding to fall under Permitted Development, it must meet several criteria:
- It must be built on less than 50% of the total garden area.
- It should not be situated forward of the principal elevation or side elevation of your house.
- The maximum eaves height should not exceed 2.5 metres if the outbuilding is within 2 metres of a boundary.
- The maximum height of the outbuilding should not exceed 4 metres for a dual-pitched roof, or 3 metres for any other type of roof.
There are also specific exemptions and limitations depending on the type of outbuilding and its intended use. For example, if you plan to use your outbuilding as separate living accommodation, such as a granny annexe, this will almost always require planning permission. However, for ancillary uses like storage, workshops, or recreational spaces, the rules are more relaxed. Here’s a quick guide to common scenarios:
| Outbuilding Type | Maximum Height | Proximity to Boundary | Notes |
|---|---|---|---|
| Shed, Garage, Workshop | 4 metres (dual-pitched), 3 metres (other) | Anywhere if under 2.5m eaves height; otherwise 2m distance needed for eaves over 2.5m. | Must not cover more than 50% of garden. |
| Summerhouse, Playroom | 4 metres (dual-pitched), 3 metres (other) | Anywhere if under 2.5m eaves height; otherwise 2m distance needed for eaves over 2.5m. | Must not cover more than 50% of garden. |
| Habitable Accommodation (e.g., Annexe) | N/A (requires permission) | N/A | Almost always requires full planning permission. |
It’s also worth noting that if your property is located in a conservation area, a National Park, the Broads, or an Area of Outstanding Natural Beauty, the Permitted Development Rights may be more restricted. In such cases, you might need to apply for planning permission even for smaller structures. Always check with your local authority if you are in any doubt about these specific designations.
To ensure you’re fully compliant and to understand the precise dimensions applicable to your specific property and location, we highly recommend consulting the detailed guidance provided by your local planning authority.