Planning permission: what do you need for your loft conversion?

planning permission - B&G Loft

Loft conversions offer a fantastic solution if you need more storage or living space. But knowing when to apply for planning permission for loft extensions can take time and effort. After all, no two projects are the same. For example, a dormer loft conversion that doesn’t require any dramatic changes might not require planning permission at all. 


Do I need planning permission?


Whether you need planning permission for a loft conversion depends on the size and style of your home, the area where you live and the type of loft conversion.

Most homeowners find that their plans fall under Permitted Development. This scheme aims to make extending your home easier without planning permission. But even if your project meets the guidelines, check with your contractor before proceeding.


What is Permitted Development?


As a rule of thumb, you won’t need to get planning permission for a loft extension if your project meets the following regulations:

  • The total area of additional space is at most 40 cubic metres for terraced homes and 50 cubic metres for semi-detached and detached properties. If you’ve already extended your home, you’ll need to include that additional space in your calculation. So if you’ve already added a 15m side extension, your loft conversion can be at most 25 or 35 cubic metres, or you’ll need planning permission. 
  • Your loft extension mustn’t be higher than the highest part of the roof or extend beyond the existing roof at the front of the house. In addition, if you’re enlarging the roof, the footprint can’t overhang the existing wall.
  • Your plans don’t include verandas, balconies, platforms and installation or alteration of the chimney. If they do, you’ll need planning permission.
  • Any side-facing windows are at least 1.7m from floor level and are obscure-glazed, so your neighbours aren’t overlooked.
  • Your home isn’t in an Area of Outstanding Natural Beauty or a conservation area.

The rules can feel confusing, especially if you’re planning your first conversion. To minimise frustrations later in the build, we recommend checking with your builder or architect that Permitted Development rights cover your project.


Will I need planning permission for a dormer window conversion?


If you’re planning a loft conversion in Essex, you need to decide on a style that gives you the space you crave. As a general rule, the more sophisticated the conversion, the more likely you’ll require planning permission.


Rooflight loft conversions

If you’re looking for a simple project that’s unlikely to need planning permission, try a rooflight conversion. Adding large windows to the existing roof and reinforcing the floor will create a usable, light-filled space with minimum hassle.


Dormer loft conversion

A dormer loft conversion creates additional space and improved head height. So it’s an ideal choice for small lofts with a low ceiling. However, you’ll need to ensure that the extension is set back 20cm from the eaves and doesn’t exceed the height of the original roof. In most cases, a dormer loft conversion doesn’t require planning permission.


Hip-to-gable loft conversions

This style of loft conversion involves extending the roof along the gable end, creating a new vertical wall. It’s a good option if you have a hipped roof, and it can dramatically affect the feeling of space. However, you may require planning permission before you go ahead.


Mansard loft conversion

Mansard loft conversions are suitable for all property types and are often used for terraced homes. A Mansard conversion involves extending the roof at a steep angle to increase the head height. However, this type of extension usually requires planning permission because of changes to the existing roof structure.


When you need planning permission for a loft conversion

Although there’s plenty of wriggle room in the Permitted Development rules, they only cover some projects. So if your planned loft conversion in Essex exceeds the limits, you’ll need to apply for planning permission.

It’s straightforward to apply online in England through the Planning Portal.  

Other situations where planning permission is required include:

  • Previously converted houses
  • Flats
  • Maisonettes
  • Buildings not intended for residential use
  • Housing created through change of use
  • Homes in areas where permitted rights and planning are restricted


Do I need a Lawful Development Certificate?

If your loft conversion is covered by permitted development, applying for a Lawful Development Certificate is a good idea. This gives you proof for the local authority or future buyers that any work was legal and met the guidelines when it was carried out. 

One word of warning. You could face fines or demolition if you convert your loft without proper planning permission. So always check with your contractor before any construction work starts.


B&G Lofts for loft conversions in Essex and London

At B&G Lofts, we’re a professional contractor offering a bespoke service to our clients across London and Essex. So if you’re planning a loft conversion, we can guide you through the process from planning permission to your finished space. Contact us today to book your complimentary consultation.