When a demolition order has become operative, the owner of the premises to which it applies shall demolish the premises within the time limited by the order, and if the premises are not demolished within that time the local housing authority shall enter and demolish them and sell the materials.
Subsection (1) has effect subject to—
section 273 (cleansing before demolition),
section 274 (power to permit reconstruction), and
section 275 (use otherwise than for human habitation).