There is a warning the cost of insurance could go up if proposed changes to the Earthquake Commission go ahead.

The Government is looking at doubling the cap on building cover to $200,000, but scrapping contents cover, and leaving it to private companies.

Labour's earthquake commission spokesperson Clayton Cosgrove said there is a danger private insurance companies will take the increased responsibility as a reason to increase premiums.

"A cynical person would say like your power bill never goes down, it always goes up. Now the question then for the government is, is it better that some of these things remain with EQC?"