City and state efforts to create more affordable housing represent a threat to the high times of New York developers, a top industry representative said yesterday.

The president of the Real Estate Board of New York, Steven Spinola, told members of the real estate industry at a Brooklyn luncheon that various new pieces of legislation push for affordable housing in an irresponsible manner that discourages development.

While luxury lofts and office towers have been shooting up around the city in a constant stream for the past few years, Mr. Spinola, who acts as the chief advocate for the city’s real estate community, denounced restrictive policies intended to create affordable housing.

“You’d be happy to build anything you can so long as there’s a reasonable return on your investment,” he said, calling for more generous subsidies for affordable housing. “We are confronted with the possibility of basically the housing market stopping.”

Mr. Spinola was reacting to both last month’s announcement by the Spitzer administration that it would cap state bonds for housing, and recent zoning changes to parts of Manhattan and Brooklyn that require developers to include 20% affordable units in new buildings over a certain height.

Also at the luncheon, which was hosted by the Brooklyn Historical Society, city finance commissioner Martha Stark criticized the city’s land value assessment system for property taxes. Currently, condominiums and co-ops built before 1974 can be taxed at substantially lower rates than houses and apartments built after 1973, when rent regulations were changed.

“You should always pay the same price on a home, whether it’s horizontal or vertical,” Ms. Stark said. The rules are 25-years-old, she added, and should be reevaluated.

Mr. Spinola also criticized the existing property tax system places an undue burden on the owners of commercial properties compared to some homeowners.