Organisers of the Rebuild and Renovate Home Show which has been cancelled because of fire at the Christchurch venue say they will lose a lot of money.
Fire broke out at the Canterbury Arena in Addington about 6.30am on Saturday triggering the sprinkler and alarm system.
The blaze took 16 firefighters about an hour to control and left the venue with extensive smoke and water damage.
The second and third days of the show are cancelled and director Amanda Magnus says ticket holders will receive refunds, but it's too early to decide what to do about the 160 exhibitors.
"There's going to be a lot of discussion around insurance and recompensing everybody that's been affected."
Ms Magnus says in 40 years of staging exhibitions, nothing like this has happened before to the organisers. About 10,500 people attended last year's inaugural show.
Darren Burden, general manager for arena manager V-Base, says exhibition stands have been damaged by water from sprinklers, and there is water in the arena itself.
"So the issue for us is to get our staff in there and the exhibitors in there to remove their exhibitions stands, and for us to clean the venue up, so that's probably going to take a couple of days."
Mr Burden says Thursday's Lionel Ritchie and John Farnham concert should go ahead as planned.