building1520 Sedgwick Avenue, where hip-hop began. (Photo: Ozier Muhammad/The New York Times)

State officials have determined that a West Bronx apartment building is eligible to be recognized on the state and national registers of historic places as the birthplace of hip-hop.

Senator Charles E. Schumer and Representative José E. Serrano joined tenants today at the building, at 1520 Sedgwick Avenue, to celebrate the determination, which came in the form of a July 5 letter from the State Office of Parks, Recreation and Historic Preservation. Normally, buildings less than 50 years old are not eligible for designation, but there is an exception for structures of “exceptional importance.”

The letter does not guarantee that the building will ultimately be judged to be a historic site, but it is a first step in that direction. To become a historic site, the building will have to go through an extensive nominating process that has only begun. The State Board for Historic Preservation will have to determine whether the building meets the criteria for becoming a historic site, and then the commissioner of the state office, Carol Ash, will have to sign off on the decision.

As David Gonzalez wrote in The Times in May, many hip-hop authorities trace the advent of the cultural movement to the first-floor community room at 1520 Segwick Avenue. It was there, in 1973, that Clive Campbell, known as D. J. Kool Herc, began turning the tables at community parties, producing a sound, a rhythm and a style that spilled out into the nearby parks and streets and, later, out into the world. Mr. Campbell was living in the building at the time with his sister, Cindy Campbell.

“Who would have thought that a place like 1520 Sedgwick Avenue, our own little Bethlehem, would become the birthplace of hip hop and would make history?” D. J. Kool Herc asked today.

In February, tenants at the building, which has 100 units, were told that the owners planned to leave the Mitchell-Lama program, in private landlords receive tax breaks and subsidized mortgages and agree, in turn, to limit their return on equity and rent to people who meet modest income limits. Tenant groups — including the Urban Homesteading Assistance Board and Tenants and Neighbors — hope the designation will help to preserve the building’s Mitchell-Lama status.

“History is made not just by the rich and powerful, but by poor and working-class and marginalized people,” said Andrew Berman, a historic preservationist who helped prepare the landmark application for the building.

flierA flier promoting a performance by D.J. Kool Herc in the recreation room at 1520 Sedgwick Avenue on Aug. 11, 1973.