Converting a barn to a home - Class Q Permitted Development
What do you need to consider?
We recently surveyed these barns for a feasibility study on the suitability for Class Q conversion.
Introduction - What is Class Q?
In summary, Class Q allows for the conversion of redundant agricultural buildings to houses without the need to apply for planning permission.
Class Q Permitted Development Rights in the UK allow for the conversion of agricultural buildings into dwellings, facilitating a smoother transition of these structures into residential properties. The legislation sits outside of normal planning policy and was designed to encourage the reuse of existing agricultural buildings, preserving the countryside's character while meeting the growing demand for housing by focusing development of housing in areas that are already developed.
The Class Q conversion process involves a set of criteria, covering aspects such as the building's size, structural integrity, and the nature of the proposed residential use. We will go into further detail on these within this post. Whilst these conversions offer exciting opportunities, it's crucial to work closely with expert consultants who are well placed and experienced to ensure that you make the most of the site and that the criteria have been understood and adhered to within the proposed design. All this will give the proposals the best chance of succeeding.
Below we have provided a brief summary of the considerations for Class Q conversions. We would always recommend that you speak to a specialist about your ideas and undertake appropriate feasibility studies on the scope of Class Q for any building or site - particularly if you are considering purchasing.
Is the barn capable of conversion to residential?
The first point to consider is the suitability of the existing structure. It is important note that Class Q assumes that the agricultural building is capable of functioning as a dwelling. Therefore it is only where the existing building is already suitable for conversion to residential use that the building would be considered to have the permitted development right. Generally Class Q applications are accompanied by a structural survey to provide evidence that the structure is suitable for conversion.
The detail required for this survey will vary between each local planning authority area. Some councils require structural calculations, whilst others are happy with just a suitably qualified professional opinion.
What alterations can you make?
In order to streamline the process, there are a number of design limitations under Class Q, with the idea being that, in principle, the existing structure retains it’s current appearance:
External dimensions - The development cannot change the external dimensions of the building, increasing the footprint or amending the extent of the external envelope.
Building operations - Under Class Q, building operations are limited to the the installation or replacement of windows, doors, roofs, or exterior walls, or the introduction of water, drainage, electricity, gas or other services, that are reasonably necessary for the building to function as a dwellinghouse. All other operations are not allowed for under Class Q.
Demolition - Some partial demolition is allowable but only to the extent reasonably necessary to carry out building operations allowed above.
Substantial alterations will require full planning permission. However Class Q can sometimes be utilised as a pre-cursor to obtaining full planning permission for adapted designs at a later date.
How many dwellings can you create?
Class Q allows for up to 5 dwellings to be created through conversion of the structures on the site, as per the criteria set out below:
Larger dwellings (For Class Q, a larger dwelling is defined as over 100 sqm)
Up to 3 no. separate larger dwellings can be achieved provided that the cumulative floor space of the existing building or buildings changing use through Class Q do not exceed 465 square metres.
Smaller dwellings (For Class Q, a small dwelling is defined as 100 sqm of smaller)
Up to 5 no. separate smaller dwellings, each with a floor area up to 100 sqm.
A Mix of Small and Larger dwellings
The maximum amount of floorspace that can be converted under Class Q on a site is 865 sqm. This can include a mixture of larger and smaller dwellings (as defined above). For example, if the Class Q proposal comprised 1 no. larger dwelling at 465 sqm and 4 no. smaller dwellings of 100 square metres. The total would be 865sqm. There are lots of dwelling mix variations below this threshold that can be accommodated.
Other Design Considerations
Design considerations for Class Q conversion include:
The design or external appearance of the building. Any design changes should be minimal and in keeping with the rural area. Any proposed changes beyond this would most likely require a full permission, and should be sought following approval of the Class Q application.
Each habitable room in the proposed dwelling(s) will need to have adequate natural light. Depending on council, they may ask for proof of this via a daylight survey.
Each dwelling proposed will need internal spaces that comply with the National Domestic Space Standards - which covers the minimum sizes (and other considerations) for rooms and spaces within a dwelling.
Whilst not a specific Class Q requirement, it is also worth noting that designs should be developed that are capable of passing Building Control once approved.
Class Q Exclusions
There are a number of designated areas where a Class Q application cannot be applied to agricultural buildings. These include:
Conservations Areas
Listed Buildings
Areas of Outstanding Natural Beauty (AONB)
World Heritage Sites
National Parks
Any sites of special scientific interest
A safety hazard area.
A military explosives storage area.
A site / building that is, or contains, a scheduled monument.
Class Q Betterment
We often see Class Q obtained on barns as a way of establishing residential use for the building / site. This can then be used to leverage a new design, which could include a completely new building, and designed in a way that works well on the site, or takes into account other important factors such as environmental impact, sustainability, future proofing for thermal comfort and affordability and passive design solutions.
More Information
Vardo Architecture is a young, experienced, creative chartered architecture studio. Our home is in Plymouth, but our work takes us all over the South West and further afield.
We are home-makers, place-makers & problem-solvers. We create individually crafted buildings for people & communities.
We specialise in transforming existing buildings with dynamic and characterful solutions. Our projects range in scale and budget, all solving our clients needs by focusing on innovative design solutions and collaboration through the design journey.
Take a look at some of our recent projects here, our services and our process here.
If you have a Class Q project in mind, then contact us to see how we can help. Whether you’re unsure about the eligibility of your property, you need help with the application process, or you’re looking for a complete architectural design service, we’re here to help.
