The cause of a massive fire tore through a seniors' complex under construction in Vancouver Friday night is, so far, not believed to be suspicious.

The fire broke out Friday around 6:40 p.m. PT at the Granville Gardens complex at Granville Street and 49th Avenue.

Deputy Vancouver Fire Chief Brian Godlonton says the cause is still under investigation.

"We had fire investigators on scene last night. They are still here now," said Godlonton.

Granville Gardens

Large portions of the 62-unit complex were gutted but Vancouver's Deputy Fire Chief says it's too early to assess the extent of the damage. (CBC)

‚Äč "They will continue to sift through the remains for the next few days. At this point in time, the fire is not deemed suspicious. However it will take another couple of days to determine the actual cause of the fire."

At its peak, flames from the fire could be seen shooting up dozens of metres into the air, and a tall plume of dark smoke rising from the site was visible across Metro Vancouver.

Godlonton says the building complex is valued at more than $10 million, but it's too soon to assess exactly how much has been lost.

He says the 62-unit building was 90 per cent complete and had a sprinkler system, but it had not yet been activated. Godlonton says it would have helped, but he couldn't say how much. The deputy fire chief says fires in buildings under construction are more intense.

"Any time the building is under construction, the fire load is  much more immense," he said. "Not all the building was completely drywalled."

He says it's believed the fire started on the third floor then quickly spread to the attic.

The fire closed down a huge stretch of Granville Street, a major thoroughfare, snarling traffic and delaying buses.

As crews poured water from above, crowds of people gathered below to watch the firefighting effort.

According to the Granville Gardens website, the complex was supposed to start welcoming new residents into its 62 suites beginning next month.

Google Maps: Granville at 49th Ave.