During a debate on affordable housing targets, Green MSP Patrick Harvie said tougher regulation is needed to ensure people had affordable rents and suitable homes.
The Evening Times has told how the city council is planning to spend £32million on one of Glasgow's most run down areas, home to hundreds of private rented flats.
The properties in Govanhill would be bought and managed by a local housing association, which would upgrade them and offer them for affordable rent.
Mr Harvie said in the debate about cash for new builds for housing association and council homes, that the tenants "trapped" in the private rented sector couldn't be forgotten.
He said: "If there is a housing crisis it is not entirely about not hav-ing suitable accomm-odation available.
"For some people they have suitable accommodation but it is unaffordable. Private sector rents are rising when incomes are either falling or static.
"Although it is a choice for some, for many it's not a choice. For many it is the only housing available. They are trapped between unavailable social rented homes and un-affordable ownership.
"The need for regu-lation of the private rented sector becomes clear. There is a case for rent controls - they are spiralling out of control and it must be brought back on the agenda."
MSPs were debating housing with Labour accusing the SNP of not doing enough to build new homes as the latest statistics showed a drop in housing association new-builds of 24% in the last year.
Labour housing spokeswoman Mary Fee said: "Scotland is facing a housing crisis that is entirely of the SNP's making. They have slashed capital spend on housing, obliterated grants for housing associations."
Housing minister Margaret Burgess said: "We are committed to 30,000 affordable homes and are making good progress.
"We are building more homes than any other administration. You can't get away from the facts - 4117 council homes while the last Labour/Liberal govern-ment built just six."
Housing associations told a problem raising finance to complement subsidies. Scottish Federation of Housing Associations expects more next year but competition for sites with the private sector would be a problem.