Listed building consent is a separate legal requirement from planning permission and applies specifically to works that would affect the character of a listed building. It covers both internal and external works, which is wider than planning permission, and it is a criminal offence to carry out such works without consent.

The Legal Threshold

Under the Planning (Listed Buildings and Conservation Areas) Act 1990, listed building consent is required for the demolition of a listed building, and for any works for the alteration or extension of a listed building in any manner which would affect its character as a building of special architectural or historic interest. The phrase "affect its character" is the key test and is interpreted broadly by local planning authorities.

External Works Requiring Consent

External works that require consent include replacing original windows with different windows, even if matching in appearance, unless the replacement is truly like-for-like in material and profile. Adding cladding, render, or any new surface finish to an exterior wall that changes its appearance or material. Any new opening in an external wall, including new windows or doors. Extensions of any size to the listed building. Changes to the roof covering using different materials. Demolition of any part of the listed structure.

Internal Works Requiring Consent

Internal works that require consent include removing or altering original features such as staircases, fireplaces, panelling, cornicing, and plasterwork. Removing or altering load-bearing walls or other structural elements. Installing new services such as wiring, pipes, or mechanical ventilation in ways that damage original fabric, for example by chasing channels in historic plaster. Subdividing rooms by inserting new partitions. Installing fitted kitchens or bathrooms in a way that removes or damages original fabric.

Curtilage Structures

Objects or structures within the curtilage of a listed building that have been within the curtilage since before 1 July 1948 are listed by virtue of their association with the main building. Works to these curtilage structures that affect their character also require listed building consent.

Summary

Listed building consent is required for all works that affect the character of a listed building, both internally and externally. This includes window replacement, extensions, alterations to original features, new openings, and works to curtilage structures. Applications are made through the Planning Portal and must explain the heritage impact and justification for the proposed works. Carrying out works without consent is a criminal offence with no time limit on prosecution.