RCMP in Port Coquitlam, B.C., say the unidentified man was with a group of friends at around 11:30 p.m. on July 11.
None of them had authorized access to the site.
Investigators say the victim was talking with friends and leaning on a temporary railing of a fourth-floor balcony when the railing collapsed, sending him plunging to the ground.
He could not be revived despite frantic efforts by his friends and by emergency crews called to the scene.
Police say the accident was avoidable and they want to hear from anyone who spots suspicious activity at a construction site, especially after hours.
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