Emergency services were called to the Bluebird Crescent property in Unsworth Heights about 2.45pm, northern fire communications shift manager Dallas Ramsay said.
"It appears a crane was moving a boat and the crane and the boat have fallen on to the house."
Everyone in the area had been accounted for and one person was being treated for a minor leg injury, she said.
The incident left the property with a hole in its roof, Ms Ramsay said.
"They're waiting for council building inspectors and WorkSafe New Zealand to attend."
It was not known if the crane and boat belonged to the house owners.
- Rebecca Quilliam of NZME. News Service