Police and Fire and Emergency New Zealand crews arrived at the Tees St fire about 3.30pm.
Oamaru station officer Jimmy Murdoch said there was a small fire in the residence, but it had been extinguished and the home ventilated.
There was no longer any risk.
Two fire appliances from Oamaru and one from Weston attended the scene.
A large amount of discoloured water flowed downhill from the site.
Mr Murdoch said that was from the hydrant, which had to be flushed out before it could be used.