Commentary on Sections Part 3 — Buildings of special architectural or historic interest Chapter 2 — Control of works affecting listed buildings Section 89 — Authorisation of works by listed building consent
316.Section 89(1) provides that works for the alteration, extension or demolition of a listed building are authorised if written consent is given by the planning authority in whose area the building is situated or the Welsh Ministers and the works are carried out in accordance with the terms of the consent including any conditions attached to it. Sections 97 and 98 make further provision about conditions attached to listed building consents.
317.The expectation is that listed building consent will be obtained before any works begin. However, under subsection (2) a planning authority or the Welsh Ministers may grant listed building consent for unauthorised works already carried out. In practice, it is only in exceptional circumstances and when the works undertaken have been for the benefit of the listed building that such consent will be granted. The applicant will need to fully justify the works in an application for listed building consent. In such cases, the works are only authorised from the grant of the consent. Any liability for an offence arising from the unauthorised works under section 117 remains and could be the basis for subsequent proceedings.