It happened on West 118th Street near 5th Avenue around 9:30 a.m. Friday.
The workers were in a boom lift 50 feet in the air in a vacant lot between two buildings apparently installing siding material on one of the buildings.
The boom lift became unstable and swayed into the building next door.
Both workers were rescued by firefighters on an extended ladder.
They were taken to Harlem Hospital with non-life threatening injuries.
The work site is now shut down, and there is an investigation into the incident.
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