A new real estate trend threatens to make the housing crisis worse than it already is for renters. But no one seems to hear the alarm.

Developers are buying up rentals in older three-story walk-up and mid-rise apartment buildings throughout Honolulu and converting them into condos for sale. In our heated housing market, it's easy to understand why.

That can be a hopeful sign for the first-time buyer opting to buy a condo because of the high price of single-family homes.

And, of course, these condo conversions mean a reduction in the the supply of rental units, which would likely mean jacked-up rents. That puts the squeeze on long-term tenants and others seeking affordable rentals.

Even if some renters have the first option to buy in new converted buildings, many can't afford it. They're not in the target demographic for the new condos in the $300,000 to $600,000 price range. Many of those renters are forced to leave.

With the state estimating it has a need for more than 17,000 affordable units, this is not a good time to see rentals rapidly being taken out of the marketplace. Surely they won't be replaced one for one.

The folks tasked with coming up with a solution here is the Hawai'i Housing Financing and Development Corporation, the new spinoff of the Housing and Community Development Corporation of Hawai'i.

That's a tall order. It won't be easy to create and preserve affordable rentals at a level that will keep pace with demand, especially if the condo conversion trend holds.

The new agency will have to come up with sensible incentives for builders that will help create a better balance — and soon. We can't afford to let our housing crisis get much worse.