Guidance for Advertisement Consent can be found at the Planning Portal Website: http://www.planningportal.gov.uk/england/public/planning/smallbusiness/bg13commontypesofapplication/bg135signsandadverts
This guide aims to explain to those wanting to display an outdoor advertisement how the system of advertisement control works in England. The booklet is arranged in separate sections and there are numerous illustrations which may show you how the system affects the type of advertisement you want to display.
The conservation polices below are most relevant:
Policy HE10 in Planning Policy Statement 5: Planning for the Historic Environment
HE10.1 When considering applications for development that affect the setting of a heritage asset, local planning authorities should treat favourably applications that preserve those elements of the setting that make a positive contribution to or better reveal the significance of the asset. When considering applications that do not do this, local planning authorities should weigh any such harm against the wider benefits of the application. The greater the negative impact on the significance of the heritage asset, the greater the benefits that will be needed to justify approval.
Wirral’s UDP Policy CH2: Development Affecting Conservation Areas
Development located within, adjacent to, or otherwise affecting the setting or special character of a Conservation Area, will be permitted where the visual and operational impact of the proposals can be demonstrated to preserve or enhance:
(i) the distinctive characteristics of the Area, including important views into and out of the designated Area;
(ii) the general design and layout of the Area, including the relationship between its buildings, structures, trees and characteristic open spaces; and
(iii) the character and setting of period buildings and other elements which make a positive contribution to the appearance and special character of the Area.
The local authority may also use discretionary powers under the terms of varying legislation to require owners to make good the condition of a property or site within a conservation area where neglect is adversely affecting amenity or threatening the preservation of character and significance, e.g. s. 215 notices.