The Downham Market blaze is believed to have started during the night where a £250,000 fire engine was parked.
The fire station, built in 2006, had no sprinkler system.
Norfolk fire service is still waiting for a full forensic study and said the inquiry was "long and complex" but an independent report had been received.
Cambridgeshire Fire and Rescue Service is assisting with the investigation and their findings reveal it is believed the cause of the fire was due to an electrical fault in one of the appliances at the fire station.
"We are in discussion with Norfolk Constabulary to consider options for a joint location at the site with shared accommodation," a spokesman said.
"We currently have temporary accommodation in place and the station is fully operational from that location."
At the outset the fire service recognised the investigation was going to be a "challenge" for experts.
The fire engine was so damaged and the heat was so intense a forensic investigation was needed but experts were optimistic they would find evidence of a cause.
Head of community safety Stuart Horth said the fire had created concerns.
"Checks have been made at other fire stations to identify potential risks and all were registered as safe," he said.
The £1m single storey fire station  was officially opened in July 2006.
It had an appliance bay where the fire is believed to have started, lecture room, offices, a kitchen and storage areas.
A year before the opening the fire station received a new state-of-the-art rescue pump.
The site was also shared with Norfolk Police and this was said at the time to be a great advantage.
An electrical fault in an appliance parked at a "state-of-the-art" Norfolk fire station caused a disastrous blaze in April last year, a report has said.