Lee Baker from West Midlands Fire Service said that, following further investigations by the fire investigations officer, they have come to the conclusion that the cause of the fire was accidental.
More than a hundred firefighters spent the night tackling the blaze at a furniture warehouse in Sparkbrook, Birmingham.
More top news
The fire service found a fire in a first-floor bedroom, and managed to put it out before it could spread to other parts of the house.
Sunshine will break through the cloud today, but showers are on the way tomorrow.
Celebrations to mark the opening are underway after the two-and-a-half-year renovation.