In most cases, yes. Works that would normally count as exempted development, such as many repairs, extensions or internal alterations, generally lose that exemption once a building is a protected structure, meaning planning permission is usually required for anything beyond straightforward like-for-like maintenance.
The general exemptions that let ordinary homeowners carry out certain works without planning permission, set out in Schedule 2 of the Planning and Development Regulations 2001 (as amended), do not apply in the same way to protected structures. Section 4 of the Planning and Development Act 2000 specifically limits exempted development for protected structures, so works that would be exempt on an unprotected house, such as some repairs, minor alterations, or changes of use, can require planning permission when carried out on a protected structure, particularly where they would affect its character.
This means renovations such as replacing windows or doors, re-roofing with different materials, altering internal layouts, removing historic fabric like fireplaces or staircases, rendering or painting previously unpainted stone or brick, and installing services like solar panels or rooflights, will very often require planning permission on a protected structure, even though similar works might be exempt on a non-protected house next door. Routine, genuinely like-for-like maintenance and repair using matching materials and methods can sometimes be carried out without permission, but the boundary between maintenance and development that affects character is not always obvious, and getting it wrong risks enforcement action.
Because of this uncertainty, owners are strongly advised to contact the local authority's conservation officer before starting any renovation, or to apply for a Section 5 declaration if there is genuine doubt about whether particular proposed works are or are not development, or are or are not exempted development. Planning applications affecting protected structures are also usually referred to the planning authority's conservation section for specialist input, and applicants are generally expected to submit a heritage or conservation impact statement alongside plans.