1. Maintenance of the HDB's approximately 900,000 units largely falls under the Town Councils, which are not part of the HDB but which are formed under the Town Councils Act primarily with the purpose of maintaining the common areas of HDB flats and estates (common corridors, void decks, lifts, water tanks, external lighting and the open spaces surrounding the estates).
2. Rental flats, on the other hand, are maintained directly by the HDB to ensure serviceability for the next occupant.
3. The HDB is also the direct authority overseeing home renovation works, whereby while home owners engage third-party contractors, the HDB imposes strict renovation rules to ensure no structural damage and adherence to noise control during renovation works. The HDB also approves renovation contractor registrations to enforce quality control
4. Large-scale improvement works to existing public housing developments were carried out in the form of various programmes under the Estate Renewal Strategy, beginning with the Main Upgrading Programme (MUP) since 1990. These help to bring common facilities up to standards with newer developments, and in some cases, to offer some improvements to individual units, such as the addition of reinforced bomb shelters which can double-up as an additional room during non-emergency periods. . . .To date, 73 sites has been affected since the Scheme was introduced in 1995, affecting over 33,000 residential units.