Notwithstanding anything contained in section eleven of the principal Act, provision may be made by an order under the principal Act for varying section ninety-two of the M1Lands Clauses Consolidation Act 1845, or section ninety of the M2Lands Clauses Consolidation (Scotland) Act 1845, as incorporated in the order in such a manner as to provide for the taking of part only of a house, building, or manufactory, except where it is shown to the authority to whom the question of disputed compensation is submitted that that part cannot be severed from the remainder of the property without material detriment thereto, but no such provision shall be made unless the Light Railway Commissioners are satisfied that special notice of the proposal to acquire part only of the house, building, or manufactory has been given under paragraph (b) of subsection (2) of section seven of the principal Act to the owner, lessee, and occupier of the house, building, or manufactory.