Barn Conversion

A Guide to Barn Conversions

Given the strict planning rules limiting the building of new dwellings in the countryside, barn conversions are becoming increasingly popular for those looking to acquire their dream home in the country. Redeveloping a barn can be an incredibly rewarding experience, creating beautifully characterful properties in idyllic locations. Furthermore, the recent changes to planning rules for barns have opened-up the possibility of residential conversion for many agricultural structures previously considered to be out of reach or unworthy. However, it is not without its pitfalls. There are numerous factors to consider before, during and after the development. It is, therefore, crucial to have a basic understanding of what will ultimately be involved in the conversion of your barn, in order to keep afloat of the planning process and realise all of your development ambitions.

We set out ten key considerations that will help you make a success of your barn conversion, while hopefully avoiding some of the potentially costly and timely delays along the way:

1. Be realistic

Many barns, whether old or modern, were built for functional purposes. Understandably then, their construction has not been developed with comfort, weatherproofing and security in mind. Consequently, many will require significant levels of refurbishment and renovation alongside the core conversion into a new residential dwelling or business space. Without losing ambition, it is therefore important to remember the multitude of additional changes that will be required alongside the mere architectural re-shaping of the building. Keeping half an eye on the fundamental nitty-gritty elements of the barn conversion while developing your proposals will ensure that your desired outcome remains not just desirable, but practical and attainable.

2. Finance and Budget Management

It’s fair to say that a barn conversion won’t come cheap. You may well pay more per m2 of floor-space than you would by constructing a new home from scratch. This is because conversion projects involve significant levels of painstaking work, often including extensive renovation and refurbishment works – all of which needs to be done while preserving original features as far as possible. However, while the costs are likely to be a little higher, a good-quality barn conversion can be hugely attractive to buyers for its inherent character.

Estimating the costs for a conversion project can be difficult, given that every project of this nature will be wildly different from the next, and the condition of the building will have a big impact on expenses. Also bear in mind though that until you begin work on the conversion, you cannot be sure of exactly what you will find.

You will also need to factor in how much DIY will be involved, as this too will influence the budget. Should the building be of poor condition, you might choose to go down the (albeit, more expensive) route of hiring a specialist construction firm. Or, you may want to take control of the bulk of the work yourself, but be prepared for the problems thrown-up by a building which was not initially built with a residential purpose.

Financing conversion projects is also not as straight-forward as standard renovations. Conventional mortgages don’t suit conversion projects, where you need funds released to support key phases of the works. Instead, your best bet will be to choose a product that works more like a stage payment self-build mortgage.

One of the most attractive features of conversions is that like new builds, they are largely free of VAT which you will be able to reclaim under HM Revenue & Customs Notice 431C. This means that if you use a VAT-registered builder, they will invoice their work and materials at the reduced rate of five percent, while any materials you buy yourself will be charged at the standard VAT rate.

Following on from the above, it’s important to remember that functional barns are usually built quickly and cheaply as simple stores, or to meet other agricultural needs. It is therefore essential to have their stability (along with other considerations such as damp and dry rot) inspected BEFORE you exchange contracts. While you can use architects or structural engineers to carry out the survey for you, most surveys will be carried out by a building surveyor who is a member of the RICS (Royal Institute of Chartered Surveying). Key areas of the building’s fabric to look over include the load bearing walls, roof structure and foundations (it’s relatively common for barns to need underpinning if you want to add a second storey, for example). Armed with this information, you’ll be in a much better position to gauge how much work will be involved, the costs and what problems you may face throughout the project – ultimately, whether conversion is viable.

4. Instruct a Reputable Architect

You may think that, with the shell of a building already in place, there’s no need to hire an architect or similar professional. In fact, conversion projects can be even more taxing at the design stages than new builds. It takes a lot of skill to maximise the potential of an existing structure, especially if it wasn’t initially intended as a dwelling.

The necessity to maximise space is especially important. Local Planning Authorities aren’t likely to accept large extensions, but smaller versions that can be demonstrated to be subservient may be permissible. A simple lean-to in a traditional style could house a utility or similar space, but contemporary additions can work well too. These provide a counterpoint to the existing barn and a clear juxtaposition between the old and new that some planners like. Oak frame is popular for this type of addition.

4. Instruct a Reputable Architect

One of the main attractions of barn conversions is the inherent and often striking character that they can bring to your new development – creating a strong backdrop upon which to overlay modern elements such as glass and suspended floors. Indeed, if there is a single rule that will lead to a successful barn conversion design scheme for a residential barn conversion, it is to be ‘TRUE TO THE BUILDING’ – in other words, to ensure that the barn retains its heritage, former purpose and essential character and form, and does not simply get turned into a house.

It’s important to keep in mind why you were attracted to it in the first place. Features such as old beams, timber cladding and beautiful stonework will bring unique character and quality to the finished result – so try to show these off to their full potential. If this simple philosophy is applied to every aspect of the design, from window and door treatments, to internal subdivision, the project should not go far wrong and should also be in line with the requirements of the local planning authority.

It’s worth remembering that the retention of a barn’s original features is not purely a matter of personal aesthetic taste. Planning Authorities in certain areas (such as National Parks and Area’s of Outstanding Natural Beauty) insist that the original character of the barn is retained, as a condition of the planning permission.

The barn form lends itself perfectly to what many people look for in a modern home — space, height and large openings for walls of glass. They allow for experimentation in affordable, interesting materials, too. Metal, timber, fibreboard and rubber can all be incorporated. Pretty much anything goes with these buildings, except trying to make them what they are not. They are not constructed from traditional house materials, for instance, so trying to reclad them in slate, tile, brick or stone will more than likely end up looking wrong.

Nor are they ‘polite’, with regularly spaced portrait windows which conform to the ‘Golden Ratio’. They shouldn’t have porches, dormers, brick chimneys or fiddly domestic details. If you do want these features, go and buy a house! If you want to go on an adventure into design and a home full of architectural interest, barns are a good bet.

If you get it right, you’ll be rewarded with a wonderfully individual, and highly saleable, property. Where you do need to introduce new materials, try to do so sensitively and with respect to the local landscape character – but don’t be afraid to put a contemporary spin on things.

6. Insulation and Re-Pointing

Most working farm buildings are un-insulated, so one of the major tasks you’ll face will be to upgrade the barn’s thermal performance to meet modern-day standards. In most cases, you are likely to want to preserve the external cladding (whether stone, brick, timber or metal), so the walls behind these features will have to be treated internally.

If you’re planning to retain vaulted ceilings, insulation will usually be fitted between the rafters (as well as beneath, if required). You’ll need to add insulative protection underfoot, too, which is likely to mean digging down through the floor to accommodate rigid boards.

Insulating timber framed barns is less of a problem for prospective developers, as the existing cladding can often be removed, and a layer of insulation added in between the frame. It is wise to re-use the original cladding where possible, both for financial and aesthetic reasons.

Should you need to repair any of the existing exterior walls, this should be done on a like-for-like basis (for reasons mentioned above). As brick or stone walls tend to be of solid construction, to meet Part L of the Building Regulations, insulation will likely need to be added to the internal face of the external walls.

An alternative to this could be to add new partition walls that are built with matching masonry to the external walls, or to achieve a seamless blend between originals and repairs, it may even be possible to repoint the whole wall, using lime mortar to retain breathability, ensuring that the removal of any original mortar is kept to a minimum.

Leaving some sections of the brick or stone fabric exposed internally can be a desirable design feature. However, because of insulation options/ requirements described above, it is usually easier to achieve this with internal partition walls, although it may be possible to clad some parts of the inner face of the exterior walls with brick or stone, forming an insulated cavity wall which can be left as a feature.

7. Essential Services

Unless you’re planning on going completely off-grid, provision will have to be made in the overall development plans for the connection to essential services. There’s a good chance your barn won’t be hooked-up to mains water, electricity, gas or drainage. It is also likely to have been derelict for some time, so any existent services may have perished by the time of purchase. Be sure to get quotes from the utility suppliers for the cost of connection, as bundled together these could easily add thousands of pounds to your budget.

This will all need to be considered in the budget. One of the benefits of this situation is that is provides the prospective developer with the opportunity to consider adopting a greener approach to energy. Open plan spaces, for instance, are best-served by underfloor heating which works well with heat pumps. Furthermore, fitting renewable options, such as heat pumps and solar electric panels, may help keep bills low.

8. Maximise Natural Light

One of the most challenging and rewarding considerations when converting a barn is the management of natural light. Barns are typically constructed with either small openings for ventilation purposes, or enormous cart door openings, so lack of light can be a problem. Successfully utilising the structure of your barn to capture and maximise all available natural light can be the difference between a bright and vibrant space, or a cavernous twilight zone which appears to lack direction.

On the main elevations, window and door openings will often be restricted (by reluctant planners) to those that already exist, so you and your architect may have to be more creative in finding ways of introducing light. On secondary elevations however, some additional doors and windows may be allowed, subject to consent.

In order to introduce natural light, barn developers have adopted numerous creative solutions, including:

  • Adding conservation-style rooflights on less prominent elevations;
  • Using glass pantiles or discreet ridge glazing;
  • Glazing entire gable ends;
  • Applying full-height glazing to cart openings; and
  • Using open-plan living arrangements.

As a rough rule of thumb, it is good to start with the light and view – locating the principal habitable rooms where the main openings of the barn are, while accepting that some parts of the building will, likely, be dark. Utility rooms, plant rooms and WC’s may only have borrowed light, but if managed well with adjacent spacious, light-filled living and circulation areas, they can be an interesting counter note in the wider composition of the design. Dark, cosier spaces may well lend themselves to snugs and living rooms used in the evening.

To avoid falling foul of the Local Planning Authority, it is wise to do all you can to avoid designing new openings into the external elevations of the barn. Where they are absolutely crucial, consider them in the same vein as the existing structure. Fewer larger openings are nearly always better than multiple smaller ones. Single openings that span between floors or rooms so that externally they appear as one opening rather than two, can help maintain a building’s integrity. Barns were not generally designed with polite symmetry in mind, they are often fairly random and asymmetric, so try and continue that in your alterations.

Most barns are a simple rectangular shape, so roof-lights are often a key option for getting light into the middle of the building while maintaining the monolithic integrity of the walls. Indeed, conservation-style roof-lights tend to be favoured as a discreet solution, and the top-down illumination they produce can transform a barn’s interior. However, here too, anything overtly domestic is the enemy, so aim for large single roof-lights, rather than multiple small ones.

9. Planning Consent

Once you have found a barn, you will need to gain detailed planning approval before you can start work. There will be some authorities that will prefer redundant agricultural buildings in the countryside to have any use other than domestic, so you may have to work hard to prove that there is no demand for the building to be re-used in a commercial capacity.

In order to remain a step ahead of the planners, carefully read their guidelines in the local authority’s local plans, which should be readily available on their website.

Where older buildings are concerned, planners typically don’t like to see significant alterations to the external appearance (as discussed above). Therefore, adopting the considerations set out earlier in this article will help ensure that your development progresses smoothly through the planning process.

Derelict barns will, quite often, be home to various types of wildlife – bats and nesting birds (specifically owls) in particular, and so a protected species survey will need to be carried out to ensure that any wildlife is not disturbed. These surveys should be undertaken by an experienced and licensed bat consultancy. Non-licensed surveyors run the risk of breaking the law by entering bat roosts and disturbing bats. Not only will this eventually render the results of the survey null and void, but it could also lead to prosecution by the respective statutory body (Natural England in England and Natural Resources Wales in Wales).

The good news is that in April 2014, the rules for barn conversions were relaxed in England. Changing the use of farm buildings to create homes is now allowed as ‘permitted development’. This means that express planning permission is no longer required; although there is a ‘prior notification’ procedure to complete. The result is that a larger range of changes of use should be considered as permitted development with the proviso that the process of prior notification for certain planning considerations of the development are first submitted to the council for determination, so that they may determine their acceptability. This in effect creates a streamlined “mini” planning application where the council has 56 days to determine the acceptability of the matters that have to be submitted for prior notification.

However, there are some significant caveats. The total floor-space of the finished development must not exceed 450m2, for example, and permitted development status does not extend to listed buildings or designated zones, such as National Parks, Areas of Outstanding Natural Beauty and Conservation Areas, in order to help safeguard the special qualities of these areas. Furthermore, permitted development rights to convert farm buildings only apply in England. Elsewhere in the UK, or for projects that involve significant works or extensions, you’ll still need to obtain full planning consent.

Even if permitted development applies to your scheme, you may still need permission for alterations such as changing the roof pitch or height, rebuilding significant parts of the structure, or inserting new windows. The government’s permitted development guidance only allows for as much work as is ‘reasonably necessary for the building to function as a house’.

If you only take one piece of advice from this article, let this be it:


Never assume that you will be granted permission, even if there seems to be a precedent set by other buildings in the immediate area. You may also need to get listed building consent, and if the barn lies within a conservation area, there’s likely to be other restrictions too.

You should ideally consult experts in the field (architects, surveyors or builders) to help you through this process. As we have said, carrying out all of the necessary building surveys before exchanging contracts will help you gauge how much work and money will ultimately be involved – although bear in mind that until you begin work, you can never be sure.

If planning permission has already been granted and is being sold with a barn and you are looking to purchase, make sure the permitted plans fit with your own. You may not be able to deviate from them when work gets underway.

10. Plan Ahead

 Many elements of the survey or construction work involved in the redevelopment of your barn will be seasonally constrained, not to mention the monthly cycles of planning committee schedules. It is often the case that prospective developers are held up for months on end, waiting for pre-determined dates or survey windows to open.

Ecology is one such consideration that is heavily constrained by seasonal timescales. One of the hurdles that must often be met by prospective developers is to undertake a bat survey. By their very nature, many old and derelict barns provide perfect habitats for roosting bats. Certain development works to these buildings therefore pose the threat of adversely affecting bats, which if undertaken without licence would be breaking the law.

In light of the amendments to national planning legislation in April 2014, many prospective barn purchasers have been prompted to ask for clarification as to whether bat, owl or other protected species surveys are still required before carrying out any barn conversion works. The answer is YES!

If your Local Planning Authority suspects that the barn may support a bat roost, they will recommend that a bat survey is undertaken before planning permission can be granted. We have put together a handy guide for understanding bat surveys as part of barn conversion developments here [link to Barn Conversion and bat Surveys Page]. For a full guide to the possible types of bat mitigation that could feasibly be required as part of your development, check out our page here.

If your barn development requires a bat survey, you must instruct an experienced and licensed bat surveyor to undertake the Preliminary Roost Assessment in order to be granted planning permission. Bat surveys generally consist of two phases, a daytime inspection (Preliminary Roost Assessment) and, if evidence of, or potential for, bats is found, activity surveys. While the Preliminary Roost Assessment component of the survey can be undertaken at any time of year, the secondary activity surveys can only be undertaken between May – September inclusive. Therefore, leaving the ecology element of your planning application to the last minute may mean that you will miss the window for undertaking stage two bat activity surveys. Your project could therefore be put on hold for up to seven months until late April/ early May.

The fully licensed bat workers at Acer Ecology are experienced in undertaking bat surveys, European Protected Species Licensing, and the creation and implementation of mitigation. You can find past examples of our work here. We operate across the West Midlands, South-West and Wales, offering a friendly, pragmatic and timely service that aims to guide your development smoothly through the planning process.

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For more information, please call us on 02920 650331, or email