The Housing and Development Board (HOB) of Singapore has gained worldwide recognition for setting high standards in public housing. To date, 87 percent of Singapore's 3 million citizens reside in high rise public apartment blocks. More than 80 percent of these apartments are owned by the residents. In 1989, the government of Singapore, through the HOB, embarked on an ambitious program to upgrade the quality of existing stocks of public housing. This paper discusses how prefabrication technology is being used to overcome the many difficulties associated with the construction of high rise apartment extensions in heavily populated areas as part of the upgrading program. The various types of precast concrete systems, used with fundamental guidelines on design for cost effectiveness and buildability, are also presented.
