Lawmaker Andrew Lam is calling on the government to make sure transitional housing projects can remain on their sites for longer, saying many residents fear having to move back into inadequate housing, like subdivided flats, once the tenancy is up.

Lam made the comment after commissioning a survey of residents who had moved from inadequate housing to transitional housing. He said half of those surveyed feared returning to inadequate housing and this was alarming.

"All this transitional housing is run by NGOs on temporary allocation of land. So the original policy is that this housing will cover five to a maximum of seven years," Lam said on RTHK's Hong Kong Today programme.

"Including the construction period... a lot of them only have three years' operation time so that's the key problem with the transitional housing arrangement."

Lam believes the situation is slightly better for light public housing but that a lot of these sites were a kind of charity by landowners.

The government has been promoting transitional housing development through the use of short-term vacant land and premises. In 2020, the Housing Bureau set up a scheme to support transitional housing projects by NGOs.

Light public housing is more government-driven and uses both government and private land. The modular temporary units, announced in the 2022 Policy Address, are also designed to house those on the public rental housing list.

Residents of both transitional housing and light public housing remain on the public rental housing list as before.

Lam said he commissioned an independent company for his survey and that it covered 14 operating transitional housing estates. He said there were over 350 responses.