The victims identified as Ibrahim and Sane Alam, both in their mid-20s, hailed from Moradabad in Uttar Pradesh and were working at an under-construction building at Lok Vihar colony in Pitampura.
According to police, the deceased used to sleep in the same building they were working in.
"On Wednesday night, following the cold weather and chilly winds, the duo arranged some small wooden logs and lit the bonfire. After having dinner, they went to sleep leaving behind the wooden logs burning inside the closed room which later claimed their lives," a police official said.
When the contractor looked for them today, he found them lying unconscious in the room and immediately called the police.
"We rushed the victims to the nearby Baba Saheb Ambedkar Hospital where doctors pronounced them dead upon arrival," the official added.