On site, Building Control determines the extent and nature of danger in accordance with Section 77 (dangerous) & Section 78 (imminently dangerous) of the Building Act 1984.
Where a building or structure is considered by the Council to be an imminent danger to the public, then the Council can take emergency measures to fence off or remove the danger.
In less serious cases the owner would be contacted to rectify the situation. If the danger is not removed within a reasonable time, legal action can be taken against the owner.
If it is considered that a building or structure (or part thereof) is overloaded or in a dangerous condition, then the Council may apply to a Magistrates' Court for an order compelling the owner either to rectify the condition or demolish the building. If the order is not carried out within the time specified by the court, then the Council may execute the order (using any method they consider applicable) and recover any expenses they incur in doing so from the person in default. That person is also liable to a fine on summary conviction. If the condition arises purely from overloading then the court can issue an order which restricts the use of the building until it is satisfied that the danger has been removed.