A listed building is a building with historical or architectural importance. A building in a conservation area might not be listed in itself, but any works that could affect the character of that conservation area must be approved by planning.
If you live in a protected building, you have responsibilities that other people don’t have. Extra levels of permission are needed for things that other people don’t have to worry about. This can include what colours walls can be painted, or what improvement works can be done.
The exact limits depend on each building, and the reasons for the building being listed. Details for any listed building can be found here:
Camden Council, as the approving authority and as a freeholder, have a responsibility towards their own listed buildings. Any changes have to take into account the building’s historic features. Emergency works can be done, but should be the minimum required. Materials used have to be approved as suitable.
Just because the Council are doing work on one of their own buildings, it doesn’t mean they can do whatever they like.