She said a full report would not be completed for the incident.
Fire investigators were also unable to confirm the cause of a house fire at Marahara on July 31.
The fire brigade was called to the blaze about 2.30am and the occupants escaped without injury.
"We couldn't rule out heat from the fireplace or an electrical fault as being possible causes," Nesbit said.
However, fire damage and the way the building had collapsed meant they were unable to confirm this.
The fire at Miller St in May has been classified as accidental. Photo / Leanne WarrThe investigation into a blaze at a workshop in Miller St in May has been completed.
The Dannevirke fire brigade was called to the blaze at Blast and Coat around 6.50am on May 10.
The fire was classified as accidental, possibly caused by an electrical event.
Information on three-step escape plans is available at www.escapemyhouse.co.nz.