CONSERVATION FRAMEWORK
5.2.4 PRINCIPLE 3: ASSESS THE IMPACT OF PROPOSED CHANGE TO UNDERSTAND THE BENEFITS OR HARM TO SIGNIFICANCE. Sufficient information about proposed change should be provided to enable the impact on significance to be assessed. This is to ensure that conflicts and risks to significance are properly managed and understood, and the potential impact of options tested. Impact does not need to be a physical intervention but can be an indirect or intangible change. It can be a major intervention or the cumulative impact of minor alterations. The impact assessment is a risk assessment tool that allows the impact of change to be objectively documented, the need for change made clear and the consequences of implementation set out. The assessment of impact is an iterative process that should be run alongside the design process. One should inform the other and proposals be revised as risks are identified and the detail developed. A final impact report should be produced prior to submission of proposals to decision-making bodies in order to understand and test the impact on significance. In line with national planning policy, the aim will be to avoid harm, which must be outweighed by any public benefits of the proposals. The process of assessing heritage impact is an essential means of ensuring that any proposed change will not cause harm to a heritage asset and will be carried out in the most sensitive way. It is vital that a careful balance is found between meeting the operational needs of a site and the significance of its built fabric, features, and spaces. Care should be taken to consider the cumulative effect of a series of minor changes. These may each appear trivial but over a period of time can disfigure the original design intent.
Assessment process for identifying the impact of change: 01 Articulate the proposals and the need for change. 02 Identify the components (tangible or intangible) of the Cathedral that are likely to be affected. 03 Assess that component to understand how it contributes to the Cathedral’s significance, using the international, national and site-specific values to make a judgment. A component may contribute to all, some or none of the values. The management gazetteer may offer the appropriate level of detail or an additional assessment may be required. 04 Assess whether there is conflict between different values or aspects of significance. The identified values of a particular component that contributes most highly to its significance should take precedence when proposing change. 05 Assess the impact the proposals will have on the component and which of its heritage values will be affected. For example, replacement of physical fabric may impact on Post-War art and design, but not on its use as an active place of worship. The key will be to balancing and resolving conflict between different values or significances.
104
06 Identify measures that could mitigate any harmful impact as part of an iterative design process in consultation with key stakeholders. 07 Assess the relative degree of harm the proposals may have on the significance of that component: a
Any proposals that would cause a substantial level of harm to the primary significance articulated by that component (and therefore total loss of understanding) would not be acceptable.
b
Any proposals that would cause a degree of harm to significance articulated by that component would need to be carefully considered for the need, justification and benefits that would outweigh the harm.
c
Consideration of the cumulative impact on the whole and a component’s setting is also required.
