A former Victorian Country Fire Authority (CFA) volunteer has been sentenced to 17 years and nine months in jail for killing 10 people by deliberately lighting a bushfire on Black Saturday.

Brendan Sokaluk, 42, was found guilty of 10 counts of arson causing death in the Victorian Supreme Court for deliberately lighting the Churchill fire on February 7, 2009.

He will serve a non-parole period of 14 years.

Outside court a relative of some of the victims, Rhonda Jacobs, said that while justice had been served, for her family nothing had changed.

"For our part it is not about hate or revenge or reprisals," she said.

"Justice has been done and seen to be done and for that we are very grateful even though sadly for us not a lot changes.

"We are without our much-loved family, and we still have a grandson without a mother, father or brother.

"Our deepest thoughts and empathy are extended to the other people who have lost loved ones, homes and property due to the terrible bushfires of 2009."

The family thanked police, bushfire recovery workers and legal professionals for showing "dignity, courtesy and respect... throughout the most difficult of times."

The verdict makes Sokaluk one of Victoria's worst killers.

On Black Saturday, the temperature in the Latrobe Valley spiked at 46 degrees Celsius and wind gusts reached 70 kilometres per hour, creating an inferno near the town of Churchill.

Ten people were killed, more than 150 homes were razed and 36,000 hectares of land were destroyed in the blaze.

Justice Paul Coghlan told the court it was a catastrophic blaze.

"The event was terrifying for all involved in the fires, whether directly or otherwise," he said.

"For the victims, these were and are life-changing events and no sentence that I impose can compensate for their loss."

'I didn't mean it'

Two cars in which two people died after a fire, started by 42-year-old Brendan James Sokaluk, near Churchill in Victoria's east, on February 7, 2009. ( Victorian Supreme Court )

Five days after the fire, police took Sokaluk back to Jelleff's Outlet, where the blaze started.

He told police he may have accidentally started the fire when he threw cigarette ash out of his car window

"Part of my cigarette thing fell on the floor, so I got a bit of paper out to grab it and stuff... I thought it was dead and I've chucked it out the window, but I didn't know it had lit up," Sokaluk told them.

The cigarette ash explanation was pivotal in what was a largely circumstantial case.

But Sokaluk strenuously denied deliberately starting the fire.

"I didn't mean any of this to happen," he told police.

"I thought it was out when I threw the paper out the window.

"I had no intention of this all to happen. Now I have to put up [with it] for the rest of my life and it makes me sad."

Sokaluk is autistic and has a mild intellectual disability.