Angela Parlane, managing director of Shine Lawyers, said the finding would not have too much of an implication.
"I don't think the fact it says 'accident' on the face of it will have too much of an implication as the insurers of the entity/person who caused the accident will still be on the hook," she said.
Parlane said an "accidental fire" was a fire where there was no proven cause as opposed to intentional such as arson.
"'Accidental fire' does not necessarily absolve an individual or entity of liability for negligence. An entity or person can still be negligent if a fire is classified as accidental."
She said insurance would normally cover such outcomes as well, depending on the policy and exclusions.
Parlane said insurers for the individuals and business involved in applying the torch-on waterproofing membrane could face legal action and potentially the manufacturers of the product as well.
The torch-on contractors were not named in the FENZ report but were interviewed at the offices of law firm Duncan Cotterill.
The Herald understands the torch-on contractors were subcontracted to water-proof membrane firm MPM Waterproofing.
A spokesman for MPM Waterproofing said: "As far as I and MPM know, there are no legal proceedings arising from the NZ International Convention Centre fire."
In a statement MPM said it had reviewed the FENZ report and believed it contained a considerable number of factual inaccuracies.
"MPM Waterproofing has voiced its concern to FENZ about the content of the report and the accuracy of the conclusions made in it. MPM Waterproofing takes the view that it would be appropriate for FENZ to retract the report while further consideration is given to MPM Waterproofing's concerns and the matter is the subject of further investigation."
Ron Devlin, Te Hiku (Auckland) region manager for FENZ, said its investigation team worked with investigators engaged by various parties involved in the New Zealand International Convention Centre construction project to ensure there was a common information base.
"Many of MPM's concerns were brought to our attention during that process. We believe they've been appropriately considered, along with all the other relevant evidence and commentary.
"This report was independently peer reviewed prior to release. While other parties are free to express their own views about the cause and origin of the fire, we are confident about the conclusions we have reached."
An insurance industry expert, who didn't want to be named, said there would still need to be proof of negligence for any litigation to go ahead.
"That is much harder to prove. The devil will be in the detail."
SkyCity and Fletcher Building have big insurance groups backing their policy cover which are likely to come with a hefty legal weight.
More than 80 per cent of the insurance cover is held by American insurance giant Chubb, with the rest held by Australia's second largest insurer QBE and Warren Buffett's Berkshire Hathaway.
Chubb operates in 54 countries and had more than US$174 billion ($273.3b) in assets.
Last year it collected US$38b in gross premiums.
QBE Insurance Group Limited is Australia's second largest global insurer and operates in Australia, North America, Europe and the Asia Pacific region.
Berkshire Hathaway is the world's largest financial services company by revenue and Buffett, its chief executive, is one of the richest people in the world.
Chubb is listed on the New York Stock Exchange and claims to be the world's largest publicly traded property and casualty insurance company and the largest commercial insurer in the US.
