Neither a council nor the Secretary of State shall start the compulsory purchase of a building under section 114 of this Act unless at least two months previously they have served on the owner of the building, and not withdrawn, a notice under this section (in this section referred to as a "repairs notice ")—
(a) specifying the works which they consider reasonably necessary for the proper preservation of the building; and
(b) explaining the effect of sections 114 to 117 of this Act.
Where a council or the Secretary of State have served a repairs notice, the demolition of the building thereafter shall not prevent them from being authorised under section 114 of this Act to acquire compulsorily the site of the building, if the Secretary of State is satisfied that he would have confirmed or, as the case may be, would have made a compulsory purchase order in respect of the building had it not been demolished.
A council or the Secretary of State may at any time withdraw a repairs notice served by them; and if they do so, they shall forthwith give notice of the withdrawal to the person who was served with the notice.
For the purposes of this section a compulsory acquisition is started when the council or the Secretary of State, as the case may be, serve the notice required by paragraph 3(1)(b) of Schedule 1 to the Acquisition of Land (Authorisation Procedure) Act 1946.