Extending projects without seeking permission: Understanding boundaries and the role of prior approval for smoother undertakings
Building Extensions in the UK: A Guide to Permitted Development and Prior Approval
For homeowners planning to build an extension, the question most frequently asked is 'how far can I extend without planning permission?' The answer lies in understanding the rules of permitted development and prior approval.
Permitted Development: Extending Without Planning Approval
Permitted development refers to regulations that allow homeowners to extend without requiring full planning approval. These regulations apply to various types of house extensions, including single-storey, double-storey, and loft conversions.
For single-storey rear extensions, the permitted development limits in the UK are:
- Up to 4 metres in depth for detached houses.
- Up to 3 metres in depth for semi-detached and terraced houses.
For single-storey side extensions, the rules are:
- Must be no wider than half the width of the original house.
- Must be single-storey only.
- Maximum height of 4 metres, with eaves no higher than the existing house.
However, exceeding these limits in depth or height, or if the combined wrap-around extension exceeds separate rear and side limits, then planning permission is required.
Prior Approval: Extending Beyond Permitted Development
If you wish to build an extension larger than the permitted development allows, you may be eligible under the Neighbour Consultation Scheme (also known as the "Prior Approval process"). This allows up to 6 metres for semi-detached houses or 8 metres for detached houses. This requires submitting details to the local authority for prior approval, which considers neighbour impact but is not a full planning application.
It is essential to note that if your property is in a designated area (e.g., conservation area, national park, Area of Outstanding Natural Beauty) or is a listed building, permitted development rights are usually more restricted or unavailable. In such cases, prior approval or full planning permission is generally required.
Building Regulations Approval: Ensuring Safety and Energy Efficiency
Even if permitted development applies (no planning permission needed), building regulations approval is still required for structural safety, energy efficiency, and other technical standards.
Simon Rix, a planning consultant, helps explain the importance of every centimetre when it comes to extensions and ways to get around limitations without applying for full planning permission. He started his career in local government and later founded Planix.uk Planning Consultants Ltd.
The process of obtaining prior approval includes a decision time of 42 days from submission, after which, if the local planning authority fails to notify a decision, the proposal is deemed to have prior approval. The current cost for a prior approval application in England is £325 (including service charge).
In summary, for a typical UK house, single-storey rear extensions can go up to 3 metres (attached) or 4 metres (detached) deep without planning permission, side extensions can be a single storey and no wider than half the house width and up to 4 metres high. Larger extensions require prior approval or a full planning application, especially under the Neighbour Consultation Scheme or if in protected areas. Building regulations must always be met regardless of planning permission.
- Understanding permitted development rules is crucial for homeowners planning to extend their homes, especially when it comes to single-storey, double-storey, and loft conversions.
- For single-storey rear extensions in the UK, the permitted development limits are 4 metres for detached houses and 3 metres for semi-detached and terraced houses.
- Side extensions, being single-storey only, must adhere to the rule of not being wider than half the width of the original house and having a maximum height of 4 metres, with eaves no higher than the existing house.
- Exceeding these limits or if the combined wrap-around extension exceeds the separate rear and side limits necessitates planning permission.
- If an extension requires more space beyond the permitted development, it may be eligible under the Neighbour Consultation Scheme, allowing up to 6 metres for semi-detached houses or 8 metres for detached houses.
- For properties located in designated areas (e.g., conservation areas, national parks) or listed buildings, permitted development rights may be more restricted or unavailable, making prior approval or full planning permission necessary.
- Building regulations approval is essential for ensuring safety, energy efficiency, and adherence to technical standards even when permitting development applies.
- To get around extension limitations without applying for full planning permission, homeowners can seek advice from planning consultants, like Simon Rix, who have expertise in home-and-garden projects and home improvement, aiming to enhance home lifestyles.
