Port Nelson says it will cost it hundreds of thousands of dollars to insulate homes affected by port noise.
The company says it is not surprised by an independent commissioners' ruling that it is responsible for minimising noise impacts on 11 affected houses.
It says it has already bought one house and will buy another, and both will be resold once acoustic insulation has been installed. The company will then work to insulate other affected homes.
The Nelson City Council says the commissioners' ruling should end a long-running environmental issue, although it is subject to an Environment Court appeal.