Class Q barn conversions: A guide

Barn conversions are becoming increasingly popular in the UK. These unique living spaces have many benefits. Among the most appealing is the potential to avoid planning permission under a permitted development right called Class Q.

Please note: There have been some changes to the regulations concerning Class Q which concern any applications being made after May 21, 2024. Read our blog on the new Class Q regulations, or stay here if you need to know about the old regulations.

WHAT IS PERMITTED DEVELOPMENT UNDER CLASS Q?

The UK government allows some types of building works to be carried out without the need to apply for full planning permission. Under Class Q, permitted development rights allow you to convert an agricultural building into a residential one (also called a barn conversion) without full planning permission.

WHAT BUILDINGS FALL UNDER CLASS Q?

In order for your chosen agricultural building to classify, it must already be in a convertible condition. In other words, it needs to be structurally suitable to be made into a habitable dwelling. If you must do lots of work to make it fit for humans to live in, it doesn’t fall under Class Q.

To put it more simply, take a moment to imagine a derelict barn in a field where only a few crumbling stone walls remain of the building. You would not be able to build a new building on top of this one under Class Q – that would be a project you’d require planning permission for.

The work you do on your barn conversion cannot result in a rebuild – either a substantial rebuild or a complete one. This is often a pitfall for many potential homeowners if they fail to do their research.

DOES CLASS Q APPLY TO STABLES?

The short answer is no. Under Class Q, your agricultural building must have been used only for the purpose of trade or a business. If the building was not used for business or has been used in part for another purpose – like domestic storage, or equestrian storage (a stable), it does not qualify.

WHAT IS THE 10 YEAR RULE FOR CLASS Q?

According to Class Q, you cannot build your own barn now and then convert it into a house. Your building must have been in use for agricultural purposes on March 20th, 2013 (or a minimum of 10 years). If it was built more recently, or agricultural use began less than 10 years ago, you must wait before converting without planning permission.

WHAT CAN YOU DO UNDER CLASS Q?

• Convert one agricultural unit into 5 small (under 100m2) or 3 large (more than 100m2) homes.

• The total floor space of the 3 large homes cannot go over 465m2.

  
  

CAN YOU EXTENDED A CLASS Q BARN CONVERSION?

You are not permitted to extend a building under Class Q. This includes extending it upwards.

If you want to add a garden or a parking area to your barn conversion, it must not exceed the footprint of the existing building.

WHAT ARE SOME EXCEPTIONS?

You will still need to apply for full planning permission if you want to convert a barn in any of the following areas:

• National Parks

• World Heritage Sites

• Areas of Outstanding Natural Beauty

• Safety hazard areas

• The Broads

• Scheduled ancient monuments

• Listed buildings

Also, if your agricultural building was initially built under permitted development rights, you cannot create a barn conversion from it under permitted development rights again.

HOW DOES PRIOR APPROVAL FOR CLASS Q BARN CONVERSIONS WORK?

If you are planning to convert a barn under permitted development rights, you still need to contact your local planning authority to get prior approval. It takes eight weeks to get an answer back once you’ve sent off your plans, surveys, and fee.

Your local authority considers the potential noise impacts, transport impacts, contamination risks, and flood related issues. They decide whether your planned barn conversion is ‘undesirable’ or ‘impractical’ in some way. The local planning authority don’t just take into account your plans for the interior of the building, they’ll also look at your plans for the exterior of your barn conversion. In addition, your proposal needs to match up to national standards for natural light and space in dwellings.

HOW LONG DOES CLASS Q PERMISSION LAST?

So, imagine your local planning authority has approved your barn conversion under Class Q permitted development rights. You now have three years to finish your barn conversion.

On the other hand, if you choose to go down the full planning permission route, you’ve got three years to beginyour barn conversion. Once you’ve started, you can take as long as you need to finish it. So if you feel that you can’t stick to a strict build schedule, it may be a better idea to apply for planning permission instead of continuing under Class Q.

WHAT IF IT DOESN'T APPLY FOR MY BARN CONVERSION?

It’s quite common for barn conversions to end up requiring full planning permission. Many fail to come under Class Q to begin with. Or the individual wants to do things that fall outside the scope of Class Q. It’s true that permitted development rights only allow for a fairly narrow scope of work. Under Class Q, you can only replace or install things that are deemed reasonably necessary to make your barn into a house. (For example: walls, roofs, doors, and essential services like drains, gas, electric and water). You are also limited on how many aspects of the existing structure you can demolish.

This essentially means that for your barn conversion to qualify for permitted development rights, you must have found a barn that is already nearly a habitable building. It must also meet the other requirements, like 10 years of agricultural use. It can be quite rare to find one of these!

If you have very ambitious ideas for your barn conversion that entail lots of changes, it’s better to apply for full planning permission. Not only does this allow you to create the home you really want, it also gives you unlimited time to do so.

BARN CONVERSIONS WITH ASTRUM CONSTRUCTION

Whether you’re looking to create your forever home or turn a profit, a barn conversion can be a fantastic investment. Find out more about the average cost of barn conversions here.

Barn conversions inherently involve elements of conservation work. Adhering to Class Q guidelines and working with the existing structure of the building differs greatly from your average construction job. That’s why it’s important to work with barn conversion specialists.

At Astrum Construction, we’ve got over 20 years of experience in barn conversions. You’re in good hands with us – contact us today to get started.