In some cases artworks may be deemed to be advertisements and may require advertisement consent. Information about whether advertisement consent is required can be found at:
In some cases your project may be classed as permitted development if it is part of a larger scheme but this should be confirmed in writing via the Council Planning Team.
For temporary projects in situ for 28 days or less it is likely that planning permission will not be required. If possible, it is recommended that you discuss the proposals to seek advice on what permissions are required