Problems of the retrofit installation of sprinkler systems in old highrise buildings: a case study

A field survey on 36 old highrise buildings in the Hong Kong Special Administrative Region (HKSAR, formerly Hong Kong) was conducted to study the problems of the retrofit installation of sprinkler systems in those buildings. The floor plan, occupancy type, number of occupants, fire load distribution, hazard class, number of sprinklers to protection area ratio and the number of sprinkler heads were studied along with the characteristics of the buildings identified. A detailed investigation was carried out in an old highrise nonresidential building with sprinkler system installed. It was observed that the retrofit sprinkler systems might not perform satisfactorily in case of fire. Further, water discharged might not reach the ground level because the sprinkler sprays pattern was not considered. Technical and financial difficulties of installing sprinkler systems in old highrise buildings were studied. In addition, it was ascertained that problems related to structural loading for the system, variation in the occupancy level, allocating spaces for the sprinkler system components such as water tank, pumps and pipes compound the complexity of installing sprinkler systems in old highrise buildings. Finally, the cost for retrofit sprinkler installation has been estimated.