There is no requirement for CCTV warning signs to be displayed along side a private domestic CCTV installation. Signage can however provide an additional deterrent and ensure your cameras are noticed by potential intruders.
With regard to a commercial CCTV installation especially where members of the public will be under surveillance, ICO guidelines state that signage should be displayed to alert the public that surveillance is in use and to provide details of the reason for the CCTV and inform them of who to contact if they have any questions about the system.
