These areas are all planned and have well developed infrastructure with spacious and landscaped ground in sharp contrast with, particularly, the low-income areas. Buildings are usually built with sandcrete blocks, and have walls and roofed with aluminium, or asbestos roofing sheets. There are also high-income peripheral areas like Haatso, Kwabenya, Pokuase, Adenta, Taifa, Mallam, where development of engineering infrastructure is not yet complete. These areas developed ahead of infrastructure, however the Achimota-Ofankor controlled-access highway was scheduled to open in May 2012, dual carriageway road construction was also due to be completed in 2012. In total, 84.4% of all houses in the Accra Metropolitan Area have their outside walls made up of cement. Similarly, houses found within Accra have 99.2% of their floor materials made up of cement.