"He sustained head, neck and back injuries and was transported to hospital in stable condition," David Sasson, a spokesman for Quebec's emergency ambulance service, said Wednesday.
"Based on what we know, he was conscious, he was breathing and he was talking to us prior and during transport to a local trauma centre."
Sasson said he did not know the extent of the man's internal injuries following Tuesday night's incident.
Bricks were still scattered on the sidewalk Wednesday as inspectors began their investigation.
The three-storey building is home to a second-hand shop on the ground floor, a cosmetics store and a tattoo parlour.
A spokeswoman for the Montreal borough of Ville-Marie said the owner of the building also visited the site with a stonemason.
"He said he would take the necessary actions required to secure the building," Anik de Repentigny said in an interview.
"The borough has required a thorough analysis of the building and it should be noted that no evacuation was necessary."
The incident comes almost three years after a 33-year-old woman was killed in July 2009 when a slab of concrete fell 18 storeys from the side of a downtown hotel.
She died when the concrete smashed through the atrium of a restaurant where she had been dining with her husband.
A coroner who investigated the tragedy released a report that highlighted deficiencies in maintenance and building inspections.