Barn Conversion into a Dwelling, a Guide following changes to permitted development rights

Farm Building Conversion Side Elevations

Do I need planning permission for a barn conversion?

Permitted development rights have existed since 2014 for a barn conversion into a dwelling. But there are some limits and there may well be other reasons for which a planning application is necessary. These are listed below:

  •  No. of dwellings – this was restricted to maximum of 3 large dwellings but in 2018 it changed to offer more flexibility. 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.
  • Amount – the agricultural unit must not exceed 465m2 to be converted under Permitted Development. You could potentially get around this by only converting part of the barn. However with the 2018 changes this could be increased with a mixture of small and large dwellings.
  • Time Pressure – Prior Approval (permitted development) applications are required to be built within 3 years. With full planning permission you have 3 years in which to start.

What are the pitfalls of a barn conversion project?

  • Also see our guide – How to Avoid 7 Costly mistakes when planning a barn project
  • Structure – Is it structurally sound? For the barn to gain permission for a conversion it will need a structural report. This will detail what structural reinforcement may be needed (eg underpinning or portal frames) and how it will be implemented.
  • Biodiversity – are there bats living in the barn? All barn conversions require a habitat survey to ensure that bats/owls/great crested newts are not living in or around your barn. If evidence of protected species are found, you will need to provide alternative habitat.
  •  Access – there are rules for how far you need to be able to see (called a vision splay) when exiting a driveway, this depends on the speed limit of the road and will need to be presented to the council.
  •  Materials – most barns are in rural areas. Therefore materials and window styles will be an important issue with the local council. They will ideally like to see something that represents the local vernacular. However modern contemporary conversions are also a possibility if they are respectful of the surroundings.
  • Contamination – the local authority may insist on a ground contamination survey as agricultural sites can often be contaminated.
  • Flood risk – If the development is in a flood zone or near to one a flood survey must be carried out and may affect the chances for development.
  • Amount of re-build. Some councils do not accept any re-build while others accept an almost entire re-build. This is often easier to agree via a planning application.
  • The Community Infrastructure Levy (CIL), though if it is intended to be your only home you can apply for exemption. If not, re-using existing floor space is exempt from CIL, if you are planning on adding a first floor or any extensions you could find yourself with a charge. See our blog on CIL here.

A pre-application can often be a good idea to test ideas with the council prior to submitting a full application. It is a quicker and cheaper way of exploring the potential options for development of your barn. This is entirely private and not available online so it is also useful for potential buyers to test the water. We offer a pre-app service.

For inspiration on your barn project you can view our recent projects here.

If you would like to speak to us about your barn project, please do get in touch.