Are there size or height limits for extensions under permitted development?
FAQ
Navigating the world of home extensions can be a bit like solving a complex puzzle, especially when it comes to understanding size and height restrictions.
When you're planning a home extension, one of the first things you'll likely consider is how big it can be. Can you add a whole new floor? Can you extend out into the garden? These are common questions that homeowners ask, and understandably so. It's crucial to know what's possible under permitted development rights before you start drawing up plans. Understanding these regulations can help you avoid potential roadblocks and ensure your extension project runs smoothly.
Understanding the size and height restrictions for extensions under permitted development can help you plan your project effectively and avoid unnecessary complications. Remember, these restrictions are in place to ensure that extensions are proportionate and respectful of their surroundings. Always consider the scale of your project, the impact on your neighbours, and the character of your local area. By doing so, you can create a bespoke design that not only meets your needs but also contributes positively to the architectural landscape of your community.
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Under permitted development rights in the UK, there are indeed size and height restrictions for residential extensions. For single-storey rear extensions, the maximum projection from the original rear wall is three metres for an attached house and four metres for a detached house. The maximum height of a single-storey rear extension should not exceed four metres. For a double-storey extension, the maximum projection is also three metres, but it must not be higher than the existing house. Furthermore, any upper-floor windows in the extension must be obscure-glazed and non-opening unless they're more than 1.7 metres above the floor of the room in which they're installed.
As for side extensions, they must be single storey, with a maximum height of four metres and a width no more than half that of the original house. Roof extensions, or loft conversions, have their own set of rules. They are allowed under permitted development rights, but the volume allowance is limited to 40 cubic metres for terraced houses and 50 cubic metres for detached and semi-detached houses. Any additional roof space created must not exceed these limits.
It's also worth noting that permitted development rights do not apply in certain areas, such as conservation areas, national parks, Areas of Outstanding Natural Beauty, and World Heritage Sites. If your property is listed or located in one of these areas, you'll need to apply for planning permission.
