Barns Permitted Development clarifications

Barns Permitted Development [2023 updated]

Barns permitted development – How big can I build a barn without planning permission in 2023?

  • You can now create 3 large (more than 100m2) or 5 smaller dwellings (less than 100m2 each) or a mixture of both under Permitted Development.

What is Class Q permitted development for a barn?

This allows you to convert a barn with a Prior Approval application with the council. So it is not quite like other permitted development (eg for a rooflight) where you can just start building!

As with all permitted development, there are quite a few restrictions. The most common hurdles are:

  • It needs to be ‘structurally sound’ for conversion.
  • It should have three or more sides (most Dutch barns don’t comply on this basis).
  • It should not need significant re-building.
  • Some barns are more desirable than others – councils have been slow to approve modern barns (see blog about this) vs prettier traditional barns.


In 2015, the Barns Permitted Development guidance, for conversion to dwellings received further clarification on what is ‘undesirable’. Previously, this was undefined giving councils the right to refuse many applications. The need for this clarification shows that some councils were not of the view that barns should be converted to homes.

However, one West Northants council officer did say to me

“It seems the government wants barns to be converted into dwellings”,

so perhaps more councils will be taking this viewpoint in future. See recent 2023 Prime Minister update on this.

For more on Barns Permitted Development see below:

For inspiration, view our barn conversion projects here

A downloadable guide on how to avoid 7 costly mistakes with a barn conversion project is available here.