Listing a building means:
Listing a building does not mean that it must be preserved and that no changes can be made to it. Listed buildings may be altered and extended, and the local planning authority will make a decision that balances the site's historic significance with other issues such as its function or condition.
English Heritage (external website) manages the listing of buildings. They are classified into grades of relative importance.
You will need consent to demolish a listed building or for any alterations or extensions which would affect its character as a building of architectural or historic interest. Applying for listed building consent process is very similar to the normal planning process. You will need to fill in listed building consent application form and provide plans. This is in addition to any other permission that may be required, such as planning permission, advertisement consent or building regulation approval.
When a building is listed it affects the whole building, both inside and out, and any later alterations to the original building that exist when it is listed.
It is a criminal offence to carry out work on a listed building without listed building consent – even if you were not aware that the building was listed. This could lead to a substantial fine or imprisonment.