Written answer by MND on correlation between use of prefab technology and incidence of water seepage in HDB flats

Jan 9, 2023

Question No: 3942

Question by: Mr Derrick Goh

To ask the Minister for National Development (a) whether the increased use of prefabrication technology has led to HDB flats becoming more prone to water seepages; and (b) whether the Ministry will consider extending the current warranty period.


We do not have any clear evidence that shows that the increased use of prefabrication technology has resulted in HDB flats becoming more prone to water seepages. In fact, HDB’s use of prefabrication technology is designed to minimise water seepage problems, while improving productivity and quality. For example, precast facades with window frames reduce seepage through the window frame by ensuring proper compaction of concrete around the frame, and cast-in pipes which prevent inter-floor seepage.

2        For new flats launched from 2005 onwards, HDB provides five years of extended warranty against water seepage from the external wall and inter-floor leaks. This 5-year warranty is above the usual industry norm of a 1-year defects liability period for both public and private projects.

3        The external walls of HDB flats are common property under the Town Councils’ management and maintenance. Residents who encounter water seepage in external walls of their flats can report it to the Town Council managing their estate. The Town Council can reach out to HDB for advice if they encounter difficulty in resolving water seepage from external walls.