Conservation principles

Learn about our guiding conservation principles, which inform our work across conservation, repairs, restoration and intervention.

Today, the principles that underpin conservation of the built environment are well developed and understood.

  • We support Historic England's* high-level principles:
  • The historic environment is a shared resource
  • Everyone should be able to participate in sustaining the historic environment
  • Understanding the significance of places is vital
  • Significant places should be managed to sustain their values
  • Decisions about change must be reasonable, transparent and consistent
  • Documenting and learning from decisions is essential

Although currently expressed in more contemporary language, these principles are the same as those of Dr John Bowes Morrell and Cuthbert Morrell when they decided to save many significant buildings in York by establishing Ings Property Company in 1945.

As well as historic significance, the long-term ability of historic buildings to "earn a living", so that they could be maintained and periodically overhauled to meet changing demands, was also crucial.

We also support, and regularly refer to, Historic England’s way of thinking about the values that make a building 'significant':

  • Evidential value: how a building reveals evidence about past human activity
  • Historical value: stories that buildings tell - connecting people and their lives, past, present and future
  • Aesthetic value: sensory and intellectual stimulation that a building can evoke
  • Communal value: all that a building means to those for whom it features strongly in experience and memory

Conservation Management

Good management and regular maintenance of buildings reduces the need for repairs. We have recently increased the capacity of our small staff team in order to achieve this. We seek to:

  • Keep an accurate and up-to date record of each building, including details of maintenance and works undertaken
  • Undertake regular inspections to a level of detail appropriate to a building’s status and complexity. We are currently engaged in the inaugural programme of Quinquennial Inspections of all buildings within the Trust’s portfolio
  • Undertake a rolling programme of maintenance for key parts of the fabric of buildings including:
  • Windows, doors and external timberwork maintained and redecorated on a rolling programme appropriate to each building
  • Regular inspection of roofs & cleaning out of rainwater gutters
  • Yards, gardens and external areas maintained and kept clean
  • External drains kept free of debris
  • Before taking on responsibility for an historic property, we will make an Assessment of Significance and record the exterior and internal fabric of the building
  • Before redecorating a building we will assess the existing colour scheme for authenticity and contribution to its aesthetic appeal and setting. If found lacking we will try to introduce a sympathetic pallet of historically authentic colours. For buildings of highest significance, we will undertake paint analysis to reveal historic colour schemes and this information will be used to inform the decision-making process


Repairing defects is preferred to restoration. Our approach is to:

  • Act promptly. When a defect is identified, remedial measures are taken as soon as possible
  • Early intervention reduces the impact of defects on a building including the likelihood of further deterioration
  • Limit repairs to the minimum required to resolve the defect and allow the repaired element to function satisfactorily. We avoid replacement wherever repair is achievable
  • Identify defects at an early stage of deterioration. Fabric should not be left to decay unnecessarily
  • Understand and research the cause of a defect before attempting any repairs. Ideally, we identify the source of a defect and repair it at the same time
  • Choose repair materials that match original fabric exactly. We try only to use substitute materials where research and understanding suggests it to be more appropriate and such use can be justified on heritage grounds
  • Use local skills wherever possible. We consider it important to retain and develop trade and craft skills in the region


Restoration is acceptable as an alternative to new interventions, subject to detailed research. We consider:

  • Reinstating missing parts of building fabric only where we have clear evidence that our proposed replacement authentically replicates original fabric. We avoid replacing fabric based on assumptions since this could lower the evidential and historic significance of a building
  • Areas of fabric to be restored very carefully. Through research and scientific analysis of materials we aim to match all historic detail exactly
  • Choices of materials and the trades / craftspeople we use in detail. A restored element of fabric will always be a facsimile and should read as such on completion. We never attempt to age restored surfaces; they should look newer and be distinguishable as later work
  • That historic buildings should not be regarded as museum pieces and that it is not appropriate for any restoration work to limit a building’s ability to fulfill its function. Buildings cannot be preserved solely for historic interest or aesthetic benefit. To have a meaningful role in society they should have a viable economic use
  • It essential that a building is fully recorded before any decisions to restore or otherwise, are reached. Also, that heritage significance is fully assessed so the impact of any proposed work can be properly evaluated


Intervention is new construction that alters or extends a building. We are not against interventions that complement an historic building and extend its viable use. We advocate that:

  • Interventions should be readable and distinct from original fabric
  • Interventions should enhance a building and be beneficial to its use
  • Alterations should balance the need for change against the significance of the historic asset. Evidential significance must be preserved; aesthetic qualities both preserved and enhanced
  • Alterations, where required solely for improvement of functionality, must be fully justified. The public benefit borne from change must outweigh potential harm caused by the development
  • Alterations that harm historical features of high or very high value should be avoided, all alternatives should be explored, and the proposed work must be fully justified
  • All interventions must be to a high standard of design – new additions must be sensitive and should complement their surroundings; this is not to say they must use the same design style, form or materials as the original. Interventions are most successful when it is clear they are not part of the original building

*“The most important places in England are listed.” Historic England

Buildings are not the only things listed as significant. Historic England lists battlefields, shipwrecks, parks, gardens, monuments and more.

Learn more about Historic England and its role in the conservation of the nation’s heritage.

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