To Build Illegal Structures or Not to Build? A Game-theoretical Explanation of the Failure of Building Control in Hong Kong

Safety has long been regarded as one of the most important functional requirements of buildings. However, building safety in Hong Kong has long been jeopardized by the proliferation of unauthorized building works (UBWs), which are essentially works constructed without any prior approval or consent of the government. Accidents involving these illegal works have so far led to hundreds of casualties in the territory. It is therefore a matter of urgency for the government to tackle the problem. Building owners or residents construct UBWs on their premises for economic gain, so the government needs to crack down on them. It is the aim of building inspection to dig out cases of illegal construction. If the cases of UBWs occur infrequently, to a certain extent the building inspection will be rendered inefficient, and thus lose its function. In this paper, a game-theoretic model for strategic control of existing buildings in Hong Kong is used to illustrate that when the level of punishment against illegal construction increases, the less frequent UBW inspections by the government will be, and concurrently, the chances of UBW construction by resident’s decreases. The model offers valuable insights into why Hong Kong’s building control system fails to solve the problem of UBW proliferation in the city.