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Recent barn conversion project under Permitted Development – Class Q



Recent barn conversion project under Permitted Development – Class Q

Base Senior Associate Joe Salt is a RIBA qualified architect, town planner and MRTPI (Member of the Royal Town Planning Institute). In this regular column, he takes a look at key planning issues and shares his experience and advice.

Here he takes a look at a recent planning success involving a permitted development change of use of an agricultural barn.

Class Q of the General Permitted Development Order (GPDO) was introduced in 2014 and was meant to provide a quicker and easier way to convert agricultural buildings to dwelling houses. The prime reason was to boost housing supply by encouraging the re-use of existing building stock and also ease the burden on the local planning authorities. Unfortunately, in practice it has done neither.

Class Q should in theory allow a de-facto planning approval to convert any agricultural building into a residential property with a few conditions and restrictions that would seem sensible, so that poorly designed or poorly located schemes are not permitted.

However, as with a lot of the provisions within the GPDO, the legislation is overly prescriptive, and any proposal requires the prior approval of the local authority before works can commence. The combination of these two elements have created a situation whereby the amount of information that is required to prove compliance with Class Q is akin to a full planning application and the statutory timeframes are identical (although with a prior notification application planning permission is automatically granted if a decision is not issued within eight weeks of validation).

The original legislation has been amended in the past few years but in broad terms Class Q allows for:

The creation of 3 no. dwellings with a maximum floor area of 465 sq.m each, or

The creation of 5 no. dwellings with a maximum floor area of 100 sq.m each

You cannot extend the building beyond its existing external dimensions and the garden area cannot be any bigger than the footprint of the building itself

You can install or replace windows, doors, the roof, exterior walls, water, drainage, electricity, gas and other services to the extent that they are ‘reasonably necessary’ for the building to be used as a dwelling

As long as it is ‘reasonably necessary’, you can undertake partial demolition

Because of the onerous nature of the legislation and local authorities’ aspirations to maintain some sort of control over development in the countryside, planning authorities have been very resistant to Class Q schemes, particularly conversions that require more than the very minimal amount of building / structural works. In short, if the building isn’t already pretty much ready to be converted with minimal structural intervention, it’s unlikely that the council will grant permission.

Base Architects has recently had success in gaining permission through the Class Q route for a steel portal framed barn which historically are incredibly difficult to obtain approval to convert, whether through a full planning application or Class Q. This is primarily because the existing structure usually cannot take the additional loading of a conversion and also because the size and scale do not naturally lend themselves for residential conversion.

An initial application was submitted and refused on the grounds that the structural works required to facilitate a conversion would be too extensive and not ‘reasonably necessary’. Following a review, we realised that most of the structural work required could be undertaken without requiring planning permission, which was confirmed in subsequent conversations with the council.

We advised the client of this, and he undertook as much of the work as possible before commissioning an updated structural report which concluded that the structural works required in order to convert the barn into a dwelling would be minimal and easily fall under the threshold of ‘reasonably necessary’. The application was then resubmitted and approved as the proposal now met all the criteria of Class Q.

Barn conversions can be exciting schemes and it is always a challenge utilising the constraints of an existing building to create contemporary spaces. Class Q does open up an alternate route to obtaining planning permission, but each scheme requires careful consideration in order to navigate the potential pitfalls and achieve a positive outcome. If you are considering a barn conversion or would like to understand your options with regards an agricultural holding, please get in touch. We would love the opportunity to work with you!

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