Heritage Impact Assessment

Heritage impact assessment is a structured process to make sure that you take the significance of your historic asset into account when you are developing and designing proposals for change. It is a core part of the design process, which tests whether your proposals for change to a historic asset are appropriate by assessing their impact on its significance. It helps to ensure that what is important about your historic asset is sustained or even enhanced when you make any changes.

You must carry out a heritage impact assessment and submit a heritage impact statement with applications for listed building consent or conservation area consent. And, you may be required to submit a heritage impact statement with an application for scheduled monument consent. This gives decision makers the information they need to understand the reasons for your proposal and to weigh up the risks and benefits. Good information, available from the outset, can speed up decisions, reduce costs and lead to better overall design.

You can also use heritage impact assessment to help you find the best way to accommodate change in other historic assets too — including registered historic parks and gardens, World Heritage Sites and historic assets of special local interest.

Heritage Impact Assessment in Wales sets out the general principles to consider when planning changes to historic assets and applying for listed building, conservation area and scheduled monument consent.

Aimed principally at owners, occupiers and agents of historic assets, this best-practice guidance also explains why, when and how to use the heritage impact assessment process and how to write heritage impact statements. It also shows how to take account of Cadw’s Conservation Principles for the Sustainable Management of the Historic Environment in Wales (Conservation Principles) to achieve high-quality sensitive change, using the principles of good design.

Decision-making authorities should also use this guidance alongside Planning Policy Wales, Technical Advice Note 24: The Historic Environment and Conservation Principles to inform their own policies and when considering individual applications for planning permission and listed building, conservation area and scheduled monument consent, including pre-application discussions.