FDNY officials have found no evidence of a smoke detector in the fire-torn Trump Tower apartment where a 67-year-old man died in a four-alarm blaze Saturday.

As investigators continued to sift through the wreckage Monday, City Councilman Robert Cornegy Jr. announced that he was drafting a bill to require that fire sprinklers be installed in older buildings, such as Trump Tower, that are currently exempt from a 1999 law requiring newer buildings to have them.

An alarm sounded as the blaze ripped through Todd Brassner’s 50th-floor apartment, but it came from a smoke detector inside building duct work, and no detector has been recovered from his apartment, FDNY officials said.

Building owners are required to install smoke detectors in units, but occupants are responsible for maintaining them, according to Department of Housing and Preservation rules.

Investigators were still combing Brassner’s home for a detector. The art dealer — who, it was revealed Monday, died of smoke inhalation — may have once had one but threw it away.

Brassner, who was once a friend to Andy Warhol, bought the unit in 1996. He had fallen on hard times recently and was struggling to sell the pad.

The 1999 law signed by then-Mayor Rudy Giuliani requires sprinklers in apartments when a building has four or more residential units but exempted existing structures. Donald Trump and other landlords successfully lobbied for the exemption.

Cornegy, who chairs the Committee on Housing and Buildings, said he would draft legislation to require exempted buildings to comply with the law.

“We have hundreds of thousands of units in New York City that fall outside of the law, and I think it’s time we bring the law up to date to protect New York citizens,” he said from the steps of City Hall.

But real-estate groups argued that existing fire-safety codes are sufficient, and the Rent Stabilization Association’s government-affairs director, Frank Ricci, said the new rules could “bankrupt” smaller landlords.

The fire, which also injured four firefighters, started in Brassner’s bedroom and appears to be an accident, officials said. They are investigating whether electrical wiring played a role.