Demand for residential areas outside the city center has resulted in strong interest in construction activity in northern Attica despite a lack of planning from authorities, according to experts in the sector. Town-planning authorities have issued 4,746 building permits in the last five years in areas north of Athens, with most interest from builders in areas such as Drosia, Dionysos and Anoixi. Experts said market needs are dictating construction expansion rates as Athens swallows up parts of northern Attica without the proper infrastructure being in place. «After this (expansion of housing) the state comes along and decides to incorporate the area into city zones without there being any scope for improvement,» Constantinos Serraos, associate professor at the National Technical University of Athens, told Kathimerini. «As a result, these areas are condemned to a lack of necessary infrastructure,» he said.