Navigating planning permission, permitted development and what you can and can’t do when converting or modifying a structure can be confusing, especially with the different stipulations and criteria that need to be met.

As structural engineers in Devon, we have worked on countless projects, all with different requirements or both structural and planning-based challenges. Here, we take a look at Class Q permitted development rights and what these permissions might mean for your barn conversion.

permitted development FAQs

What is Class Q Permitted Development?

Permitted development grants planning permission to your project without you having to make a planning application, which can be an arduous process.

Class Q rights make it possible to convert barns and other former agricultural structures into residential buildings without the need for full planning permission.

In this respect, barn conversion development is simpler than building new homes in rural areas as you won’t have to seek the same level of consent to build. This, however, does not mean that there aren’t restrictions and rules in place to ensure potential Class Q projects are appropriate.

how get planning permission for agricultural land

Getting Class Q Prior Approval

Although Class Q removes the need for planning permission, a prior approval notice must still be brought to the attention of the relevant local authorities.

The notice must include details of any alterations to the external appearance, among other proposed changes. Refusal can be made on the grounds of it being undesirable or impractical or if the authority does not feel that plans fall within the Class Q credentials.

Therefore, it is often advised to employ the advice of a professional as they can also help you appeal should your application be refused.

The roof of a converted barn

What is the Criteria for Class Q Permitted Development?

Are your works permitted under Class Q rights? You pay attention to the following criteria and rules.

  • The site must have been used solely for agricultural purposes on or before 20th March 2013.
  • Cumulative floor space of existing buildings or the proposed development cannot exceed 465 square metres.
  • New development cannot exceed more than five dwellings. You can build up to three large homes, each greater than 100 square metres with the overall floorspace reaching 465 square metres, or up to five smaller dwellings where each home is no greater than 100 square metres, or up to five homes of differing sizes that don’t exceed the threshold.
  • The land must not be occupied by agricultural tenants unless consent from both landlord and tenant is given.
  • Permissions are not granted if agricultural tenancy is terminated less than a year before development begins.
  • Class Q development cannot be carried out if Class A or Class B development has been executed since 20th March 2013.
  • Development must not result in the external dimensions extending beyond the dimensions of the current building.
  • Replacing or installing windows, doors, roofs, exterior walls, water, drainage, electricity and gas services all fall under the Class Q rights.
  • Mezzanines and new flooring are not included in Class Q permissions.

Planning authorities will also make a clear distinction between conversion and rebuilding, so make sure you are not planning to rebuild the existing structure beyond operational development.

Other Class Q Restrictions

You will not receive Class Q rights if any of the following categories apply to your site:

  • Listed buildings
  • Conservation areas
  • Areas of Outstanding Natural Beauty
  • National Parks
  • World Heritage Sites
  • Sites of Special Scientific Interest
  • Safety hazard areas
  • Military explosive storage area
  • Sites that contain scheduled monuments

When Can You Start Building on Your Agricultural Site?

The prior approval procedure requests that local authorities must determine an application’s result within 56 days of receiving it. However, do not assume consent has been granted if this deadline is not met; you should always wait to hear from the authorities before commencing any work.

do I need a structural engineer

If you’ve got a barn conversion project on the horizon, chances are you’ll need a structural engineer to survey the proposed building and assist with any structural changes. Our team here at Martin Perry Associates has worked on an array of conversion projects, working closely with planning professionals to ensure each structure is more than a success.

Get in touch to find out more about how we could support you and your upcoming structural project or conversion in Devon and Cornwall.