The 1970s

• 1970
  First Income Ceiling Raise
  The income ceiling for application of an HDB flat was raised for the first time from $1,000 to $1,200 and the maximum mortgage loan repayment period was extended. HDB would raise its income ceiling several times in the years ahead as the standard of living of Singaporeans improved with the country's growing economic prosperity.

• 1971
  Resale of HDB Flats
  Flat owners were allowed to sell their HDB flats in the open market upon fulfilling a stipulated occupation period, instead of selling their flats back to HDB. This meant that flat owners could earn some proceeds from their HDB flats as well as allowed others an opportunity to buy a resale HDB flat.

Introduction of 5-Room Flat Type
HDB also introduced a new 5-room flat type which had a higher income ceiling than that for other flat types, to cater to Singaporeans' aspirations for bigger homes.

• 1973
  Ang Mo Kio
  Work began on Ang Mo Kio, marking the third stage of HDB's town development. HDB's prototype town model had been consolidated, and Ang Mo Kio was planned on a new hierarchical structure. It thus had in addition to the town centre, neighbourhood centres and sub-centres as well as better facilities.

1974
Zoning of HDB towns
The zoning register system was introduced to overcome the shortcomings of the individual register system. It divided towns and estates into geographical zones and applicants could select their preferred zone. They would subsequently be offered flats in the towns and estates under the zone they had selected when their number was due.

• 1978
  Special Housing Schemes
  Three special schemes to encourage extended family ties were introduced - the Joint Balloting Scheme, the Mutual Exchange of Flats Scheme and the Reside Near Parent/Married Children Scheme. Of the three, the Joint Balloting Scheme which enabled related families to apply for flats together in the same/neighbouring town or estate, would achieve the greatest measure of success.

• 1979

Introduction of Executive Flat Type
The Executive flat type was introduced to cater to a new group of middle-income public housing applicants. Along with this, an income ceiling of $3,500 was set for the Executive flats, while the income ceilings for 3/4-room and 5-room flat types were raised to $1,500 and $2,000 respectively.