loft room planning permission

Do I Need Planning Permission for a Loft Conversion?

It is possible to do a loft conversion without applying for planning permission if certain conditions are met?

Provided your loft conversion meets these conditions, it will be considered 'Permitted Development'.

A Loft Conversion within Permitted Development

Generally, your loft conversion will be 'Permitted Development if it:

  • Is less than 40 cubic metres (terraced houses) or 50 cubic metres for semi or detached houses
  • Does not have dormers or structural changes to the front elevation of the house
  • Will not be higher than the existing roof
  • Does not include any balconies

This is a simplified list which will apply to most houses, but if you live in a listed building, a conservation area or on 'designated land' then you may still need planning permission for your loft conversion.

An example of a loft conversion which does not require planning permission would be where a dormer window was added to the back of the house only. If the dormer is not taller than the highest part of the existing roof and is set back by at least 20cm from the eaves, it would fall within permitted development.

Loft Conversions Requiring Planning Permission

Examples of loft conversions where planning permission would be required are:

  • Dormer windows to the front elevation of the house
  • Hip-to-Gable conversions when raising ridge height
  • Mansard Conversions

Getting planning permission can be a complicated process, but here at Amazing Loft Conversions we have a lot of experience with planning applications and we manage the whole process for our clients.

Planning applications require, as a minimum:

  • A drawing showing the location of the house on an Ordnance Survey Map
  • A plan drawing of the property
  • Elevation drawings of the house in its current state
  • Elevation drawings of what the house will look like once the conversion is finished
  • Proof of ownership of the house
  • A completed application form
  • A fee of at least £200

There are both national and local requirements for planning applications, so your local planning authority may have additional criteria which need to be met.

A planning application will typically take 8 weeks to be reviewed by a planning authority, but it can take longer in some cases.

The planning authority will consider how your house will look after the conversion is complete, but also how the changes will affect your neighbours. They will be asking questions like:

  • Will you be able to see into other people's houses?
  • Will you be blocking light from entering neighbouring gardens?
  • Are the changes in keeping with the existing house / nearby houses?

If planning permission is granted, it may come with conditions, such as designating a loft conversion as an 'office' and not a bedroom.

You can find out more information about the planning process on the planning portal ( <LINK REQUIRED> but if you choose to use us for your loft conversion project we will manage the whole process for you.

Should I Avoid Planning Permission for my Loft Conversion?

A loft conversion is a serious undertaking and we do not advise changing your plans significantly just to avoid planning permission.

If your ideas for your dream loft conversion are only slightly outside permitted development, then it may be worth tweaking them to save you time and money and we can help you to do that.

There are additional costs which come with a planning application (for drawings and fees etc) but relative to the total cost of a loft conversion project, they are quite small.

The time required to process a planning application can be frustrating, but ultimately the loft conversion will be in place for decades, so waiting an extra 8 weeks is not a huge problem.

Planning permission is not the only regulatory hurdle your loft conversion can face, be sure to read this article here about general rules and regulations affecting loft conversions.


Here at Amazing Loft Conversions, we will manage your loft conversion project from start to finish; we will take your ideas and turn them into a working design and then build it for you.

Click here to discuss your loft conversion project today.



Share this post
Need help with your Loft Conversion project?
request a quote
View More Posts

Latest Posts





envelopephone-handsetchevron-downarrow-right linkedin facebook pinterest youtube rss twitter instagram facebook-blank rss-blank linkedin-blank pinterest youtube twitter instagram