The fire, in the south shore suburb's borough of Saint Hubert, started in a semi-detached house at 6534 des Marronniers Street.
It spread to the home next door, then crossed to two neighbouring semi-detached homes.
One of the homes was reduced to three feet of brick rubble and a smouldering wood frame, while the three others suffered extensive damage, including blown-out windows and caved-in roofs.
Fifteen people from the four burned homes all fled in time and suffered no injuries. Another 15 people in surrounding houses were also forced to flee to safety.
A neighbour interviewed by CBC News said they heard what sounded like an explosion before the flames erupted.
Once the site is safe, both fire and police investigators will start to examine what caused the fire.