The board decided that owners of apartments renting for more than $1,000 a month would get no vacancy allowance.
In many cases a normal vacancy allowance and rent-guidelines increase will be enough to put the legal rent at $2,000.
Until then, landlords can get both the vacancy allowance and the 20 percent increase, according to the state's ruling.
A second generation could keep the apartment and rent protections, but only by agreeing to pay the increased vacancy allowance.
But vacancy allowances raise the cost to new tenants.
The vacancy allowance now in effect is 10 percent; in October it goes to 12 percent.
In those cases, no vacancy allowance may be charged.
There would be no vacancy allowance for units renting for more than $1,000 a month.
"I believe that the vacancy allowance is not necessary because the owners are able to cover expenses through other increases allowed under the rent-stabilization system."
The vacancy allowance comes on top of the regular rent increases permitted under the rent-stabilization law.