Designs on your listed building

    Upgrading or rebuilding a listed building can be a planning nightmare if you don’t know what you are doing. In the latest of his regular columns, architectural designer John Bullock offers advice on how to avoid the pitfalls, and how talking to experts will help save you valuable time and money

    John Bullock Design

    Dear Design with the Times,

    We are in the process of moving out of London and buying a house that is just outside Tunbridge Wells.

    The house we are buying has been owned by the same family for over 40 years, and although it has been reasonably well maintained, it needs updating and quite a lot of work to make it into something that would work for us.

    Upstairs there are five bedrooms and a family bathroom, and we would like to add an en-suite bathroom and dressing room to the master bedroom. We don’t mind losing a bedroom for this.

    On the ground floor the layout is a little awkward as it doesn’t have a really good family kitchen/dining room.

    As a family we spend a great deal of time together and enjoy cooking and entertaining, and we would like to create a large, light-filled space that leads out on to the garden.

    We feel the only way we can create this is to add an extension. The house also needs completely upgrading as the electrics and plumbing are ancient.

    Outside there is also a small, detached brick outbuilding. We have a lot of friends who would like to visit us in Kent and we would like to create a small annexe with a bedsitting room and bathroom where they can stay and be a little independent.

    We are also thinking ahead, and ultimately this could be used for elderly parents sometime in the future.

    The current garage block is a horrible 1950s concrete sectional building comprising three bays, and we would like to replace this with an oak-framed open-bay garage that we feel would be more appropriate.

    And we would then like to enclose one of the garages with large doors for the safe storage of our garden machinery.

    In the garden there is also an old swimming pool which we will refurbish, and we would like to build a tennis court.

    We have just found out that the house is a listed building (Grade II) and wondered if this would cause a problem for us obtaining permission for any of the works?

    I understand that as a Grade II listed building we can do anything inside without permission. Is this correct?

    Henry and Jessica,
    Tunbridge Wells


    Owning a listed building can be a real pleasure and joy. But owners of historic buildings are also its custodians, and it is important to understand a building to ensure that the brief is fulfilled without damaging the integrity of the listed structure, and maintaining it for future generations to enjoy.

    There is a very common misconception that with a Grade II listed building it is only the external envelope that is listed and you can make any changes to the interior without obtaining planning or listed building permission. This is incorrect and potentially any alteration will require consent.

    We asked Mark Stephenson, Principle Conservation Officer at Tunbridge Wells Borough Council, to clarify the position.

    “As a starting point, I would emphasise the following: A building is listed under the Planning (Listed Buildings and Conservation Areas) Act 1990 for its special architectural or historic interest.

    “When a building or other structure is placed on the list it is given a description, the content of which is primarily for identification. What the description is not intended to do is identify what parts of a building are listed.

    “Once a building has been listed, the whole of the building, inside and out, is considered to be listed and therefore protected.

    “Listing can extend to including some outbuildings, garden features, walls or enclosures, and where this occurs these structures are also protected.

    “The Act 1990 also requires that works of demolition or alteration of a listed building that affects its special architectural or historic interest require listed building consent, a process administered by the Local Planning Authority.

    “It can be argued that the removal of a single brick and its replacement with a brick of a different colour, texture or size is an alteration that could affect the special architectural or historic interest and therefore requires a consent.

    “In practice, there is a level of ambiguity in determining exactly what does and does not require consent, and in many cases this can come down to the individual building itself. It is therefore difficult to give generic guidance on this subject.

    “Given that unauthorised works to a listed building are a criminal offence, if you are proposing any work to your listed property, it would be prudent to first check with your local planning authority as to the need for consent.”

    This might all sound rather onerous, but it isn’t. The key here is to work closely with the local conservation department and engage with them at an early stage to discuss ideas about what might or might not be possible to take on board, and work with their advice.

    By doing this, the best results will be achieved both to fulfil the brief and also preserve the integrity of the listed building.

    When clients buying new houses approach us, and when it is possible, we always encourage them to move in and live with the building for a few months before crystalising their plans for alterations and extensions.

    This offers them the opportunity to understand the spaces, how they relate to one another, how they work or don’t work, and how the light works at different times of the day.

    This knowledge is important and can then inform the brief, and ultimately the resultant design.

    On listed buildings, Mr Stephenson recommends: “When considering works of alteration, demolition or extension to your listed building, the starting point is to understand the significance of the many parts of your building and of the building as a whole.

    “Significance can be derived from the age of the physical parts of the building, the materials used, the sequence of change over time, the level of craftsmanship, the quality of design, its representation of particular architectural fashions, representation of society at a particular time (social context), association with famous individuals, innovative technologies, the setting of your building, the architectural form (shape of the building), massing (solidity and relationship of shapes) and scale (relationship with its surroundings), and so on.

    “Different aspects of your building may have very different levels of significance. All will contribute to the significance of the building as a whole.

    “Significance, therefore, is far more than simply the appearance of the building, but also derives from its very fabric, its design, its relevance to history and its setting.

    “Once you understand the various levels of significance of your building, you can then work out where changes you would like can be accommodated, and the impact that will have on the overall significance of your property.

    “This should be the starting point for all decisions you subsequently take when considering how you wish to change your building.

    Historic England has good advice on its website if you are interested in learning more. Visit

    John Bullock Design 2

    “For your local conservation officer, the appropriateness of your proposals will be determined using the following processes:

    • Where does the significance lie for the existing building?
    • How has the proposal been developed and how has it reacted to significance?
    • What is the impact of the proposal on significance (beneficial or harmful)?
    • If there is harm, what is the level of harm?
    • Is there a good reason for that harm (justification)?
    • What is the balanced outcome (level of harm versus level of justification)?
    • Are there alternatives, or can improvements be made, to the proposal to reduce harm?

    “The ambition is to produce proposals that cause no harm to the significance of your building.

    “Given that this is the process your local conservation officer will generally follow, it would seem logical that when you are considering your proposals you follow the same process, and that your analysis is clearly shown in your application generally through a heritage statement and a design (and access) statement.”

    So, there is a great deal to consider, but with professional guidance and advice this is in fact all fairly straightforward.

    Your potential new home has a great deal of character and we have worked on many similar projects. Let’s take the points individually:

    Tennis Court: The position of this in context with the listed building has to be carefully considered and I would suggest moving this as far away as possible from the house.

    Given the size of garden there appears to be sufficient space for it to sit comfortably on a north/south axis within the residential curtilage.

    It is the court fence which will have the most impact, and this triggers the need for a planning application.

    It is also worth considering the colour of the court, as a green colour is more likely to blend in with the garden than a blue or red one.

    Garage: The existing garage is unsightly and sits uncomfortably with the house. A new oak-framed garage structure incorporating a store could have significant benefits, and whilst it will have a pitched roof instead of the existing flat roof, it could significantly improve and enhance the setting of the listed building.

    It might also be worth considering adding a small ‘cat-slide’ roof area to one side, which will add character, and also can be used as a log store.

    Outbuilding/Annexe: Although it is set a little way from the house, this structure is potentially curtilage-listed. We would need to seek guidance on this.

    It is within planning policy to convert outbuildings to ancillary accommodation, and if it is cartilage-listed, the conservation officer would be keen to ensure its conversion is not detrimental to it or the setting of the listed building.

    With careful design, this could create a really good asset which would preserve the building and put it into use. I would suggest keeping it fairly simple with an open-plan sitting room and bedroom with en-suite.

    Extension: In principle, an extension should be acceptable, but it is crucial to consider this in context of the existing structure; not only in terms of scale, mass and bulk but also in design.

    Over the past few years we have undertaken many extensions to listed buildings, some traditional in form and others with a more contemporary approach.

    A large family kitchen/dining room and entertaining space is now part of how we all live, and to achieve this the key is to look at what is appropriate, to be flexible in the design, and not to have too many preconceived ideas as any extension should be site-specific in its design.

    See Historic Scotland’s advice on extensions at

    John Bullock Design 3

    Internal Alterations: It looks like there is currently a door between bedrooms one and two; utilising this and creating an en-suite and dressing room in bedroom two would be the most logical solution.

    Installing new plumbing and electrics does not generally require listed building consent in dwellings, but any alterations to the fabric of the listed building might.

    Therefore it is prudent to discuss with your electrician and plumber how they intend undertaking the works – in particular, how new cable and pipe runs will be installed and if any new opening in the external walls will be required for flue pipes or externally-run drainage and soil pipes.

    The best approach is to engage with a professional at an early stage and pull together a master plan for the entire property.

    This would include an appropriate level of assessment of significance, drawings of the design proposals and layout of the site to show how the whole relates to the existing.

    Once this has been defined, then an approach to the conservation officer for informal ‘pre-application’ advice can be made. It is likely that the conservation officer would wish to visit the site and assess any potential impact.

    Although there is a fee payable for this service, it is a worthwhile process as it will give a clear indication at an early stage as to whether the proposal will be acceptable or, if not, what other parameters there might be to fulfil the brief.

    Once the design approach has been agreed then formal planning and listed building applications can be submitted, and hopefully permissions granted.

    This process takes around eight weeks, and then discussions with builders can commence.

    Tunbridge Wells Borough Council provide excellent advice on planning and listed buildings, and our thanks go to Mark Stephenson for his contribution to this month’s article.

    John Bullock

    If you have a question you’d like John Bullock to answer, then please email it to: or

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    Design Team
    Times of Tunbridge Wells & Tonbridge,
    16 Lonsdale Gardens,
    Tunbridge Wells
    TN1 1NU

    Having studied at Edinburgh College of Art and The Royal Academy of The Hague, John Bullock launched John Bullock Design in 2003. With offices in Tunbridge Wells High Street, John has won awards for his work and is committed to delivering the best outcomes for clients.