TABLE OF CONTENTS - The Professional Green Building Council

Theme B: Creating a livable, healthy and environmentally viable citiesFigure 2:Traditional Method of Construction of Housing Blocks during 1970’sIn Hong Kong, there were over 250 nos. of public housing blocks constructed in thisway during the period of 1970’s to 1980’s, ranging from 7 stories to 20 storiesbuildings. These blocks have been under an extensive maintenance programme overthe years in tackling concrete spalling, recasting of concrete elements and evensubstantial strengthening works. The annual expenditure for concrete repair is in theorder of HK$2M to $3M per year. The table below shows the repair cost trend.Table 1: Cost Trend of Concrete RepairAge of Blocks(years)Handover YearNo. of BlocksCompletedCost of Repairper flat per year(HK$)Total Cost ofConcrete Repairper year (HK$)31 -- 35 1972 ~ 1976 60 301 1.9M26 -- 30 1977 ~ 1981 194 158 3.1M20 -- 25 1982 ~ 1987 219 15 0.4MThe life cycle of the earlier domestic blocks have been typically in the range of 40 to50 years when the maintenance cost is continually increasing. Because of the needto go for more high rise redevelopment due to the scarcity of land and the upgradingof living standard through enlarged flat sizes, the majority of these earlier blocks havebeen progressively demolished under the Housing Authoriity’s ComprehensiveRedevelopment Programme. From the sustainability point of view, compared withother structures like bridges which have the life of over 100 years, this is a significantcost tag to the society and should be improved.383