Ynys y Pandy Slate Mill


Listed Building Consent

Guidance for Listing Building Consent Applications

Listed Building Consent is needed for any alterations, extensions or demolitions that affect the character of a listed building. This applies to all parts of the building including objects and structures, interior or exterior, regardless of grade and whether or not the feature is mentioned in the official list description. It may also apply to associated buildings that are within the curtilage of the principal building. Curtliage buildings are ones which form part of the land attached to the listed building and have done so since before 1 July 1948. This will include boundary walls. It is a criminal offence to carry out such works without first acquiring the necessary listed building consent.

While the listing of a building is not a bar to future change, the starting point for the exercise of listed building control is the statutory requirement on local planning authorities to ‘have special regard to the desirability of preserving the building or its setting or any features of special architectural or historic interest which it possesses’.

A properly documented application should be made on forms provided by the local planning authority. It should describe the situation, how the proposals will change it and have enough clear detail about what is intended to enable a full understanding by the officer considering the application and those to be consulted. There is no provision for consent to be granted in outline.

The onus for drawing up the application lies with the person charged with preparing it and where there is uncertainty about requirements it would be best that they consult or employ an architect or surveyor with conservation experience. The Royal Institute of British Architects, for example, will be able to supply lists of suitable architects or practices.

If the work you are proposing involves extensions or change of use, you may also need planning permission and Building Regulation approval. If other permissions are required, it is best to submit your applications at the same time.

Applicants should indicate whether the property to be altered has received grant assistance from Cadw, or if any application for grants has been submitted and is pending decision.

Nature of Proposed Works

Paragraph 69 of Circular 61/96 advises:

‘Applications for listed building consent must be able to justify their proposals. They will need to show why works that would affect the character of a listed building are desirable or necessary. They must provide the local planning authority with full information, to enable them to assess the likely impact of their proposals on the special architectural or historic interest of the building and on its setting’

If you wish to discuss your proposal before preparing detailed plans, or have any questions about what is required, an officer of the Authority will be pleased to help you and the following telephone numbers may be of assistance: 01766 772208 or 01766 770274

Drawings should be accurate and properly detailed and annotated. How extensive they are will depend upon the extent of the alterations which you have in mind. Whether major or minor, the alterations need to be accurately depicted. A qualified building professional, such as a draughtsman, would best know how to convey information to someone who has not seen the site.

Plans should be drawn to an appropriate (metric) scale. For plans, sections and elevations 1:50 is usually adequate (with floor plans at 1:100 in the case of large buildings), but doors, windows, and other decorative features such as railings may require 1:20 or 1:10, particularly important details may need to be half or full size.

These, and any perspective drawings and reconstruction that some proposals may need, must be cross-referenced to maps and plans. Because of their ‘mechanical’ nature, computer (CAD) generated drawings are seldom appropriate when dealing with historic buildings. Measured drawings should be used in conservation work because of the detailed complexity of old buildings.

Well-chosen dated photographs can be helpful, but they should supplement rather than replace what can only be properly shown on accurate and detailed drawings.

Written material should describe matters that cannot be covered on plans, such as the architectural significance of the building, the justification of the proposals and any conservation method statements.


In all planning or listed building applications the basic context needs to be shown by describing:

  • the location of the development site or building in relation to the surrounding area (a map based on an Ordnance Survey extract at 1:1250 or 1:2500), the site or building should be edged in red and any other neighbouring land in the same ownership in blue.
  • how the proposal relates to the listed building as a whole, the site and buildings on or near to it.
  • the type of proposed development or works, its general form and characteristics.

As Existing

‘As existing’ information about historic features affected should cover:

  • the grade and age of the building
  • its particular aspects or elements affected by the proposals – for buildings, shown in drawings of floor plans, elevations and sections as relevant, at a scale of 1:50 (floor plans can be 1:100). If only a small part of a building is affected by the proposal, detailed drawings of that part should be provided together with a general drawing showing its relationship to the rest of the building.


No fees are payable to the Authority for submitting a Listed Building Consent application.

Conditions of Consent

If applicants receive consent, there may be conditions attached. You will need to read them carefully and make sure you can comply with them before starting work. You should give your builder or contractor a copy of the consent and approvals before he starts work or before he tenders for a contract. It is an offence in law not to comply with conditions of listed building consent.

Building Recording

When listed building consent has been granted, it may not be possible to start work until you have notified the Royal Commission on the Ancient and Historical Monuments of Wales. By law, you must give the Commission one month notice of works of demolition or substantial alteration and allow its staff reasonable access to the building so that they may, if necessary, make a record of the building before work begins.

In some cases where the Authority considers that an essential part of the character, or a substantial part of the historic fabric of the building will be lost, a condition that recording work must be undertaken prior to commencement of work will be part of your listed building consent. Details of what recording is required will be provided after you receive your decision notice.

Cadw's Role in the Listed Building Consent Process

Cadw: Welsh Historic Monuments is the executive agency within the National Assembly with oversight for the historic environment of Wales. It has no separate legal identity from the Assembly and will not act in a manner that may prejudice any future involvement of the Assembly in the planning process. Primary responsibility for planning matters relating to listed buildings rests with the local planning authority and applicants should contact this planning authority and not Cadw for any advice. Cadw’s professional staff may offer informal advice to the planning authority if specific guidance is sought to assist in the decision making process.

If the planning authority decides to refuse consent, it may do so without referring the case to Cadw. In such cases the applicant has a right of appeal to the National Assembly. In certain cases where a local authority intends to grant listed building consent it must notify Cadw of the application. The notification process presents the National Assembly, on the advice of Cadw, with the opportunity to call in the application for determination. Cadw has a statutory period of 28 days from receipt of the application to decide whether to refer the application back to the planning authority for determination or give notice that further time is required in which to consider if the application should be called in. The Assembly will only call in cases which raise significant issues or which may be controversial.