http://www.legislation.gov.uk/ukpga/1968/72/section/74/enactedTown and Country Planning Act 1968Planning (town and country)Planning applicationsListed buildingsBuilding alterationsStructure plansKing's Printer of Acts of Parliament2022-02-03 Town and Country Planning Act 1968specified amended provision(s)The Constitutional Reform Act 2005 (Commencement No. 11) Order 2009art. 2commencement order for 2005 c. 4. This amendment not applied to legislation.gov.uk. The Town and Country Planning Act 1968 (c. 72) is held on legislation.gov.uk in pdf format only and it is not possible to revise the textTown and Country Planning Act 1968Blanket AmendmentConstitutional Reform Act 2005Sch. 11 para. 1(2)s. 148(1)art. 2(d) PART VI 74 Notwithstanding anything in section 12 (2) (a) of the principal Act (carrying out of works for the maintenance, improvement or other alteration of a building not to constitute development if it is wholly internal or does not materially affect the building's external appearance) the carrying out of works for the alteration of any building by providing additional space therein below ground shall, if begun after the commencement of this section, be treated for the purposes of the principal Act as involving development.