For five years, delivery driver Mohammad Suhaimi Junaini, his wife and their two daughters aged six and two called a rental flat in Telok Blangah home.

Last September, the 32-year-old and his family moved to a three-room flat in Jurong West.

Mr Suhaimi, who is the family's sole breadwinner and earns $1,300 a month, had applied for the $200,000 flat in November 2017 as he felt it was better to buy a flat than pay $250 in rent every month.

The flat would also "provide the family with security" should anything unforeseen happen to him, he said.

He received $70,000 in housing grants, and took a $100,000 Housing Board loan to buy the flat.

His family is one of the 3,500 rental flat tenants who bought a flat in the Build-to-Order or Sale of Balance Flats exercises over the past six years from 2013 to last year, said the HDB yesterday.

Of these 3,500, about 2,000 tenants have moved into their new flats, HDB said. It added that about 600 rental tenants become home owners each year on average.

First-timer families who meet the eligibility criteria and buy a flat from the HDB can receive up to a maximum of $80,000 of housing grants, comprising the Additional CPF Housing Grant of up to $40,000 and the Special CPF Housing Grant of up to $40,000.

The HDB also provided a breakdown of the 3,500 rental tenants who became first-time flat buyers.

Three in four bought either a two-room flexi or three-room flat, with 47 per cent buying three-room flats and about 28 per cent choosing two-room flexi flats. The rest bought flats of other sizes.

About 72 per cent of the group bought a flat with the help of the Additional CPF Housing Grant (AHG) or the Special CPF Housing Grant, or both.

First-timer families who meet the eligibility criteria and buy a flat from the HDB can receive up to a maximum of $80,000 of housing grants, comprising the AHG of up to $40,000 and the Special CPF Housing Grant of up to $40,000.

The HDB added that about 20 per cent booked a flat under the Tenants' Priority Scheme. Under the scheme, the HDB sets aside 10 per cent of flat supply in sales exercises for eligible public rental tenants, as well as for other applicants whose flats are affected by the Government's resettlement or redevelopment programmes.

Meanwhile, rental tenants who opt for a resale flat can receive up to $110,000 in housing grants. This comprises the CPF Housing Grant of up to $50,000, AHG of up to $40,000 and the Proximity Housing Grant of up to $20,000.

National University of Singapore sociologist Tan Ern Ser said the Government has been giving housing grants to enable rental tenants to eventually own their own flats.

These grants, when coupled with measures aimed at training and helping the adults to secure jobs, and with support for childcare and the children, "could contribute to preventing their being entrenched in rental housing, while enhancing the social mobility chances of both the adults and... their children", he said.